HSUK vs HS2

[TheGuy77]

Since HS2 has had many cuts thanks to the incompetent government, I was wondering: Is HS2 still a good idea, or should we build Colin Elliff and Quentin MacDonald's High Speed UK instead? Both schemes cost around £50B, and while HSUK says there is more to offer with their network, while HS2 says their trains will be as fast as 225mph. So, what do you think?

 

[Grimsby town]

Since HS2 has had many cuts thanks to the incompetent government, I was wondering: Is HS2 still a good idea, or should we build Colin Elliff and Quentin MacDonald's High Speed UK instead? Both schemes cost around £50B, and while HSUK says there is more to offer with their network, while HS2 says their trains will be as fast as 225mph. So, what do you think?

There's no way HSUK costs £50bn. HS2 is half built and HSUK is lines on a map. HSUK has morphed into something that would cost trillions at this point.

It also relies on a lot of interaction with the existing rail network which would need long and disruptive upgrades. It seems very similar to the German ICE network, with direct services from everywhere to everywhere. Given ICE's reliability, I don't think it is a model the UK should be aiming for.

 

[Darandio]

The HSUK website is basically every fantasy idea ever posted on this forum presented in a spaghetti of crayon.

 

[6Gman]

The HSUK website is basically every fantasy idea ever posted on this forum presented in a spaghetti of crayon.

Wonderfully put!

I have tried contacting HSUK, asking some pretty innocuous questions about some of their proposals.

Not a peep in reply.

Which suggests their plans are hardly robust.

 

[skyhigh]

Is HS2 still a good idea, or should we build Colin Elliff and Quentin MacDonald's High Speed UK instead?

Given that hundreds of millions have already been spent on HS2 and work is underway, why should we bin off all that and go for a fantasy proposal instead that's nowhere near build stage?

 

[NoRoute]

Is HS2 still a good idea, or should we build Colin Elliff and Quentin MacDonald's High Speed UK instead?

That would be HS2, designed to provide a high-speed link and additional capacity between London Euston, Birmingham and the major cities of the North - Manchester, Liverpool, Leeds, Sheffield, Derby, Nottingham. Where the costs are so high it is now unclear whether it will get to Euston and when or even whether it will ever reach any of the cities other than Birmingham.

Is it still a good idea? Clearly not, as it stands today it's looking like a pretty epic failure that if it was not already in progress, would in hindsight never have been given the go ahead in its current form. But that said, HS2 was sanctioned, it is in-progress and vast sums have already been spent so it's now really a question of what can be salvaged from it, to provide some benefits and leave the potential that it might achieve its original objectives at some undefined point in the future, if a government is willing to throw a lot more money at the project.

But the reality is there's no funds available to build anything else or complete HS2 in its original form, so the likely future of HS2 for at least the next decade or two is to be a very expensive, over-specified southern by-pass for the WCML.

Both schemes cost around £50B, and while HSUK says there is more to offer with their network, while HS2 says their trains will be as fast as 225mph. So, what do you think?

Only they don't, that's why HS2 has had such huge problems and required continual cuts to the deliverables and scope of the project because the cost is considerably higher, to the point that the full project cost appears highly uncertain.

 

[BogiePicker]

I'm very interested in HSUK and I'm surprised by the ferocity of opposition to it, on a railway website of all places.

For me, it is the fact that Mr Elliff had explicit and systematic objectives from the off which is of fundamental importance. No mission creep or piecemeal planning like HS2. This is an absolute cardinality in strategic planning.

It is untrue to say that it is unmapped.

Given that HSUK has aimed at comprehensive interconnectivity between every 'principal centre', including crucial national links to Heathrow, I think we could sink the HS2 costs and still win with this.

It also relies on a lot of interaction with the existing rail network which would need long and disruptive upgrades. It seems very similar to the German ICE network, with direct services from everywhere to everywhere. Given ICE's reliability, I don't think it is a model the UK should be aiming for.

HSUK probably won't cost 50bn but you have to look at when it was costed. Interaction is to provide direct HS services to secondary and tertiary centres. Funnily enough Grimsby Town would be served 1tph, running nonstop to Nottingham and then off to Lincolnshire on classic lines. Four tracks would help with resilience and the flipside of interaction with the network is many more diversionary routes than HS2.

I would also guess that the bulk of flows would be along the standalone HS new builds. You would have segregation between HS and local services in core urban centres (eg Leeds fourtracking from Farnley Viaduct to Cross Gates).

Looking at Greengauge21 reports. Interestingly, they interviewed Colin Elliff thoroughly and fairly in their report 'Fast Forward', but rejected the 'reverse E' format and four-track HSL.

But later, they brought out 'Beyond HS2' with explicit criticisms of HS2 limitations (specially the piecemeal planning which left many lacunae in the network) and suggestions which are core to HSUK, such as HS Cross Country services via New St and redirection of WCML to Crossrail to vacate Euston (and thereby enable platform capacity for four-tracked HSL).

 

[The Planner]

I'm very interested in HSUK and I'm surprised by the ferocity of opposition to it, on a railway website of all places.

For me, it is the fact that Mr Elliff had explicit and systematic objectives from the off which is of fundamental importance. No mission creep or piecemeal planning like HS2. This is an absolute cardinality in strategic planning.

It is untrue to say that it is unmapped.

Given that HSUK has aimed at comprehensive interconnectivity between every 'principal centre', including crucial national links to Heathrow, I think we could sink the HS2 costs and still win with this.




HSUK probably won't cost 50bn but you have to look at when it was costed. Interaction is to provide direct HS services to secondary and tertiary centres. Funnily enough Grimsby Town would be served 1tph, running nonstop to Nottingham and then off to Lincolnshire on classic lines. Four tracks would help with resilience and the flipside of interaction with the network is many more diversionary routes than HS2.

I would also guess that the bulk of flows would be along the standalone HS new builds. You would have segregation between HS and local services in core urban centres (eg Leeds fourtracking from Farnley Viaduct to Cross Gates).

Looking at Greengauge21 reports. Interestingly, they interviewed Colin Elliff thoroughly and fairly in their report 'Fast Forward', but rejected the 'reverse E' format and four-track HSL.

But later, they brought out 'Beyond HS2' with explicit criticisms of HS2 limitations (specially the piecemeal planning which left many lacunae in the network) and suggestions which are core to HSUK, such as HS Cross Country services via New St and redirection of WCML to Crossrail to vacate Euston (and thereby enable platform capacity for four-tracked HSL).

Of course its unmapped and would cost more!

 

[6Gman]

Of course its unmapped and would cost more!

It is "mapped" in the sense that someone has drawn lines on a map.

Whether those lines make any practical sense is another matter entirely.

As a retired train planner I would say that the analysis undertaken by HSUK is the equivalent of my going outside, licking my finger, sticking it in the air and giving you a weather forecast for the next ten days.

 

[HSTEd]

I would have preferred something less ambitious, in its opening, than either HS2 or HSUK.

West Midlands Shinkansen for example, northern terminus in Wolverhampton running down the M1 corridor.

 

[Grimsby town]

I'm very interested in HSUK and I'm surprised by the ferocity of opposition to it, on a railway website of all places.

For me, it is the fact that Mr Elliff had explicit and systematic objectives from the off which is of fundamental importance. No mission creep or piecemeal planning like HS2. This is an absolute cardinality in strategic planning.

It is untrue to say that it is unmapped.

Given that HSUK has aimed at comprehensive interconnectivity between every 'principal centre', including crucial national links to Heathrow, I think we could sink the HS2 costs and still win with this.




HSUK probably won't cost 50bn but you have to look at when it was costed. Interaction is to provide direct HS services to secondary and tertiary centres. Funnily enough Grimsby Town would be served 1tph, running nonstop to Nottingham and then off to Lincolnshire on classic lines. Four tracks would help with resilience and the flipside of interaction with the network is many more diversionary routes than HS2.

That's part of the problem. I love the place I was born and its difficult to argue that it doesn't need better infrastructure and rail services but a direct HS rail service is crazy. Presumably it would be operated by 186mph 200m units. This is for a line that had a 2 hourly Class 153 five years ago.

Again I don't think the French approach to HS rail is sensible either. Trying to serve every small town with direct HS services will produce a high subsidy system. The original HS2 proposals struck a good balance between the number of areas served and the amount of services using existing infrastructure.

 

[mike57]

Am I missing something here...

We cant build the original concept HS2 because the costing was way off and project management seems to have failed, and its been cut back to a 'lets just finish the bits we have started' with even Euston in doubt. So how is a much expanded HS network proposed by HSUK going to be funded.

I have to say HSUK looks like fantasy.

I think we got HS2 wrong from the start, some of the decisions just dont make sense, but HSUK doesnt look feasible.

 

[Sad Sprinter]

West Midlands Shinkansen

That reminds me of the hilarious "Ongar Shinkansen" joke from London Reconnections years ago

 

[dosxuk]

Both schemes cost around £50B

No, they don't. There is not a chance in the world you could buy the amount of land and perform the number of upgrades they suggest for anywhere near £50bn. While HS2 may be designed for higher speeds, that isn't the main cost of the project. Land take, something which HSUK will need to do more of, is a much bigger contribution to the cost.

Even just building the dedicated line from London to Liverpool & Edinburgh will cost significantly more than that.

I'm very interested in HSUK and I'm surprised by the ferocity of opposition to it, on a railway website of all places.

The opposition comes from it being a complete pie-in-the-sky idea with zero credible basis in reality.

No mission creep or piecemeal planning like HS2. This is an absolute cardinality in strategic planning.

You will need to get politicians involved at some point. And the treasury - unless this is entirely going to be funded privately. At which point you will get mission creep, piecemeal planning and scope changes by the plenty.

 

[Sad Sprinter]

I'm very interested in HSUK and I'm surprised by the ferocity of opposition to it, on a railway website of all places.

Railforums, despite being a train enthusiasm forum, is actually a semi-professional railway forum. So things like HSUK might not be as impressive to others as it would be to a casual "Hornby and nostalgia" enthusiast as myself

 

[HST43257]

With a crayon in hand I often feel the ideal is a morph between IRP and original HS2+NPR, with the HSUK section from Darlington to Glasgow being the high speed route to Scotland. Some rough calculations suggest that Manchester to Glasgow would be quicker via this route than the current mainline somehow, even calling at Leeds, York, Newcastle and Edinburgh on the way. I also reckon there’s potential for 2h35 London to Edinburgh and 3h00 London to Glasgow even if you call at York, Newcastle and Edinburgh.

 

[Sad Sprinter]

With a crayon in hand I often feel the ideal is a morph between IRP and original HS2+NPR, with the HSUK section from Darlington to Glasgow being the high speed route to Scotland. Some rough calculations suggest that Manchester to Glasgow would be quicker via this route than the current mainline somehow, even calling at Leeds, York, Newcastle and Edinburgh on the way. I also reckon there’s potential for 2h35 London to Edinburgh and 3h00 London to Glasgow even if you call at York, Newcastle and Edinburgh.

I've always liked HSUK's triangular junction idea in Yorkshire to route Manchester to Sheffield and Manchester to Leeds traffic over one trans-pennine spine through Woodhead (roughly). Of course, Bradford would get missed out in this routing.

Do I feel a new "design your high speed railway" speculative thread coming on? I really do...

 

[BogiePicker]

With a crayon in hand I often feel the ideal is a morph between IRP and original HS2+NPR, with the HSUK section from Darlington to Glasgow being the high speed route to Scotland. Some rough calculations suggest that Manchester to Glasgow would be quicker via this route than the current mainline somehow, even calling at Leeds, York, Newcastle and Edinburgh on the way. I also reckon there’s potential for 2h35 London to Edinburgh and 3h00 London to Glasgow even if you call at York, Newcastle and Edinburgh.

I think the routeing axis of a very fast northbound high speed line to North Yorkshire - Tyneside - Edinburgh - Glasgow is one of the strongest parts of HSUK, as it allows one to meet many objectives simultaneously.

You drastically speed up services to London, Heathrow, Liverpool, and Birmingham/Bristol, but by placing Glasgow and Edinburgh on the same axis you use paths much more efficiently and can have higher frequencies (and don't have to spend more money enhancing the West Coast corridor from Crewe northwards). Proposed Glasgow/Edinburgh to Manchester and Liverpool are 2 & 1 tph respectively, much greater than at present, and you would still get from Liverpool to Glasgow faster than the current West Coast route as you'd travelling almost twice as fast.

Your assessment is accurate: HSUK would have fastest journey times of 2h 30 and 2h 50 from London to Edinburgh and Glasgow respectively, with a single stop in Newcastle. When coupled with direct HS services to Heathrow, this would seriously reduce domestic Anglo Scottish aviation. Given one has accepted the Glasgow - North Yorkshire routeing, it surely makes more sense to speed more or less due south rather than veer west to Birmingham; the environmental costs of HSL construction are more greatly mitigated by the substutited flights, against which, in my view, the benefits of continuously running HS trains are maximised.

That's part of the problem. I love the place I was born and its difficult to argue that it doesn't need better infrastructure and rail services but a direct HS rail service is crazy. Presumably it would be operated by 186mph 200m units. This is for a line that had a 2 hourly Class 153 five years ago.

Again I don't think the French approach to HS rail is sensible either. Trying to serve every small town with direct HS services will produce a high subsidy system. The original HS2 proposals struck a good balance between the number of areas served and the amount of services using existing infrastructure.

Well, what the Grimsby service really amounts to is a super-fast nonstop London-Nottingham service, extending as a shuttle off to Newark (via a restored link), Lincoln, Grimsby, Cleethorpes. Greengauge21 certainly think Grimsby deserves a London service (East Lincolnshire report).

I've always liked HSUK's triangular junction idea in Yorkshire to route Manchester to Sheffield and Manchester to Leeds traffic over one trans-pennine spine through Woodhead (roughly). Of course, Bradford would get missed out in this routing.

Do I feel a new "design your high speed railway" speculative thread coming on? I really do...

For Bradford, the proposals would be a new tunnel for Halifax - Rochdale non stop running, (ie Manc - Rochdale- Halifax - Bradford - Leeds and beyond via fourtracked Aire Valley) and southbound access to Sheffield, Birmingham, and London via a reactivated Spen Valley route.

 

[HSTEd]

There isn't really much point to a high speed line on the west coast north of Manchester.
It's not far to Preston and after that there is precious little in the way of population until you reach the Scottish Central Belt.

Going via the North East gets you a far greater population for the bulk of the route, because the population density doesn't really drop off until north of Newcastle.

And even at 300km/h you are eating up five kilometres every minute, so marginal reductions in distance traveled are inconsequential in the grand scheme of things.

To be economic high speed rail has to go where the people are.

245km from Preston to Motherwell with only Lancaster and Carlisle, or 145km from Newcastle to Edinburgh.

To compare, a Manchester-Glasgow alignment gets you Preston, Lancaster, Carlisle and Motherwell.
A Manchester-Edinburgh alignment gets you Leeds, Middlesbrough and Tyneside.

 

[Sad Sprinter]

There isn't really much point to a high speed line on the west coast north of Manchester.
It's not far to Preston and after that there is precious little in the way of population until you reach the Scottish Central Belt.

Going via the North East gets you a far greater population for the bulk of the route, because the population density doesn't really drop off until north of Newcastle.

And even at 300km/h you are eating up five kilometres every minute, so marginal reductions in distance traveled are inconsequential in the grand scheme of things.

To be economic high speed rail has to go where the people are.

I don't disagree, but I thought the accepted wisdom on this forum is that a high speed line HAD to go via the West Coast? I would have thought lumping Glasgow/Edinburgh passengers onto one train to London made the most sense in order to fill seats. There's only 500,000 or so passengers a year travelling from Euston to Glasgow by train.

 

[BogiePicker]

For comparison, there are around 2 million flights a year between the London airports and Edinburgh and Glasgow each (4 million total). A single London airport will probably match the Euston total for Glasgow. A lot to be hoovered up. Assuming 4,000 operating hours a year for simplicity, that is 1,000 an hour or 500 per direction. You can imagine that HSUK superfasts to London Euston and Heathrow would soak up a lot of traffic. And the freed up domestic slots would allow for more heavy widebody aircraft to wider international destinations; this is strategic thinking in action.

An east-sided HSUK route would also allow you tack on the not-inconsiderable Aberdeen and Inverness flights via Edinburgh Airport, Forth Bridge, and Perth, upgraded routes to which are strongly desired not only by HSUK. A West Coast route precludes this as well.

I don't disagree, but I thought the accepted wisdom on this forum is that a high speed line HAD to go via the West Coast? I would have thought lumping Glasgow/Edinburgh passengers onto one train to London made the most sense in order to fill seats. There's only 500,000 or so passengers a year travelling from Euston to Glasgow by train.

 

[Sad Sprinter]

For comparison, there are around 2 million flights a year between the London airports and Edinburgh and Glasgow each (4 million total). A single London airport will probably match the Euston total for Glasgow. A lot to be hoovered up. Assuming 4,000 operating hours a year for simplicity, that is 1,000 an hour or 500 per direction. You can imagine that HSUK superfasts to London Euston and Heathrow would soak up a lot of traffic. And the freed up domestic slots would allow for more heavy widebody aircraft to wider international destinations; this is strategic thinking in action.

An east-sided HSUK route would also allow you tack on the not-inconsiderable Aberdeen and Inverness flights via Edinburgh Airport, Forth Bridge, and Perth, upgraded routes to which are strongly desired not only by HSUK. A West Coast route precludes this as well.

This also doesn't include air traffic from Bristol and Southampton too to Scotland. Which isn't exactly tiny.

However one reason why I favour a west coast alignment is because of the potential to run high speed trains from Scotland into Manchester Airport. Coupled with high speed trains from Birmingham, Liverpool and Leeds, Manchester has the potential to become the true hub airport for much of the United Kingdom instead of Heathrow.

 

[The Planner]

For comparison, there are around 2 million flights a year between the London airports and Edinburgh and Glasgow each (4 million total). A single London airport will probably match the Euston total for Glasgow. A lot to be hoovered up. Assuming 4,000 operating hours a year for simplicity, that is 1,000 an hour or 500 per direction. You can imagine that HSUK superfasts to London Euston and Heathrow would soak up a lot of traffic. And the freed up domestic slots would allow for more heavy widebody aircraft to wider international destinations; this is strategic thinking in action.

An east-sided HSUK route would also allow you tack on the not-inconsiderable Aberdeen and Inverness flights via Edinburgh Airport, Forth Bridge, and Perth, upgraded routes to which are strongly desired not only by HSUK. A West Coast route precludes this as well.

How much of the air market are you expecting to soak up?

 

[HSTEd]

I don't disagree, but I thought the accepted wisdom on this forum is that a high speed line HAD to go via the West Coast? I would have thought lumping Glasgow/Edinburgh passengers onto one train to London made the most sense in order to fill seats. There's only 500,000 or so passengers a year travelling from Euston to Glasgow by train.

This argument appears to be based on the idea of getting the fastest possible journey to Scotland.

The problem is that you will never fill a west coast HSL, so the cost per seat is probably going to be enormous.

 

[Sad Sprinter]

This argument appears to be based on the idea of getting the fastest possible journey to Scotland.

The problem is that you will never fill a west coast HSL, so the cost per seat is probably going to be enormous.

This is always why I favoured a Birmingham through station. Such a station could at least link with the cross-country network and pick up pax from Bristol, South Wales and Gloucestershire. Oxford and Nottingham too. A Manchester airport to Glasgow corridor could serve the airport itself as well as Liverpool passengers too, assuming a Liverpool to Manchester high speed line was built.

To be honest, this is also why I favoured a route via Heathrow, at least for Anglo-Scot trains. Aside from the airport, it could provide connections into Surrey and Hampshire via the Heathrow Southern Link. With these connections, anyone west of the high speed line wanting to head into Scotland could fill the remaining seats that Londoners themselves haven't filled.

 

[BogiePicker]

This also doesn't include air traffic from Bristol and Southampton too to Scotland. Which isn't exactly tiny.

However one reason why I favour a west coast alignment is because of the potential to run high speed trains from Scotland into Manchester Airport. Coupled with high speed trains from Birmingham, Liverpool and Leeds, Manchester has the potential to become the true hub airport for much of the United Kingdom instead of Heathrow.

Another strength of HSUK is that it can serve the growing Bristolian economy very well because of the New St routeing (and even offer a Cambridge - Bristol service via Heathrow!)

HSUK would provide very good coverage to Edinburgh airport anyway. Manchester Airport could in principle be reached from east coast (Leeds - Stockport - Man Air) anyway. Routeing choice.

How much of the air market are you expecting to soak up?

With a sub-3hr journey time between London and Edinburgh-Glasgow, it is reasonable to suggest a good fat chunk. In Japan, the Shinkansen between Tokyo and Osaka apparently has 80% market share with a similar journey time. But here is another second-order strategic element: HSUK's 'Heathwick' (integrated Heathrow Gatwick operations via 15min connecting HSL newbuild) + freeing up domestic slots for more international variety and frequency will make London more competitive vs European rivals Amsterdam Schiphol and Paris CDG. This means that HSUK isnt just competing with domestic Anglo-Scottish flights - also competing (really Scottish-Heathrow HSL) with overseas connecting flights!

 

[Grimsby town]

Well, what the Grimsby service really amounts to is a super-fast nonstop London-Nottingham service, extending as a shuttle off to Newark (via a restored link), Lincoln, Grimsby, Cleethorpes. Greengauge21 certainly think Grimsby deserves a London service (East Lincolnshire report).

But there's a bit of a difference between a couple of 130 metre Class 800s services a day and an hourly 200m HS train. I completely back the former, I think the latter is a bit mad and massively overkill for what the line needs. Why the need for a direct train? Why not a regular connecting 4 carriage train. A HS line should be used to free up capacity in the ECML for secondary destinations like Grimsby. It shouldn't be used to serve secondary destinations itself.

 

[eh_oh]

This HSUK plan is aboslutely bonkers and there's no way it would cost any less than double HS2.

There is merit to going east coast north of Leeds/Manchester, but this could be done via HS2 eastern leg or NPR anyway

 

[HST43257]

This HSUK plan is aboslutely bonkers and there's no way it would cost any less than double HS2.

There is merit to going east coast north of Leeds/Manchester, but this could be done via HS2 eastern leg or NPR anyway

Which is why it’s completely crayonistic, but in a world that things had happened I think they were surely the natural next step

 

[BogiePicker]

But there's a bit of a difference between a couple of 130 metre Class 800s services a day and an hourly 200m HS train. I completely back the former, I think the latter is a bit mad and massively overkill for what the line needs. Why the need for a direct train? Why not a regular connecting 4 carriage train. A HS line should be used to free up capacity in the ECML for secondary destinations like Grimsby. It shouldn't be used to serve secondary destinations itself.

Some points:

1) I don't see why we need to be wedded to the TSI philosophy of running trains in 200m multiples - I think even Watkins himself would not have insisted on a direct continental service from Grimsby! No recent domestic trains do that anyway, and it would not be optimal for Birmingham New St, for example. HSUK Heathrow services would in fact run as at least 100m x 2 because of the platform limitations at Central and T5. There are very high speed trains (200mph) which run as relatively short sets. The E6 Shinkansen is 20m x 7 = 140m and trundles along at 80mph max along the classic lines to quite rural Akita in Japan; and the articulated AGV is as short as 132m according to Wiki. If you will, the 574kmh TGV was of 2 + 3 formation, so would probably have been around 85m.
2) I must repeat that it would not be a dedicated Grimsby express... There is already a 0.5tph to Lincoln from LKX, so imagine reducing the travel time to there by ~30mins, routeing it via the much larger Nottingham rather than Stevenage and Pboro, and sending it off to Grimsby and then Cleethorpes, which already gets an hourly TPE service IIRC. I have to re-emphasise that the bulk of the flows would very naturally be for Nottingham, and there would be no upgrades beyond getting a fast connection from Nottingham to Newark, just to reassure you! And for the avoidance of all doubt, 2tph to Nottingham would remain, only that the fast train would be around 45 mins faster, so no demand dilution from greater frequency. You aggregate flows by routeing efficiently, ending up with a Nottingham + Lincolnshire express and a Lincolnshire REX. I must say that I am slightly baffled to see someone so determined that their hometown not receive a rail service from London!
3) One must not underestimate the effect of having a direct uninterrupted intercity service, above all to London.

Believe it or not, Grimsby is not absolutely pivotal to HSUK...if demand isn't there, can just drop it...just illustrates what is possible, I think 22tph max flows across a four track mainline demonstrates the capacity to provide services like this.

This HSUK plan is aboslutely bonkers and there's no way it would cost any less than double HS2.

There is merit to going east coast north of Leeds/Manchester, but this could be done via HS2 eastern leg or NPR anyway

1) One has to compare like for like. If we are just comparing London to Manchester & Leeds, route mileage is less because you're using a single spine up to South Yorkshire and integrating the transpennine leg into the North-South leg, rather than forking outside Birmingham and then building another transpennine line on top of that. So instead of building two fast lines to Manchester, from Birmingham/Crewe and Leeds, you're only building one (from Sheffield/Penistone), and the distance between Birmingham and Manchester, is short enough that you can use affordable upgrades to the existing lines to achieve sub-hour journey times, and this includes an essential stop at Stoke.
2) The thing is that you are getting at least double anyway, since you are building four tracks rather than two, but saving money by building them along the same corridor. OTOH HS2 believed 4 tracks would eventually be needed to satisfy anticipated capacity, but its 18tph max is looking very very busy indeed compared to HSUK's around 22tph from London with double the tracks.
3) Given one's accepted the Glasgow - Edinburgh - Newcastle - Darlington/North Yorkshire routeing, why is it so bonkers to head more or less due south straight for London rather than veer west to Birmingham and then steer east again with a stop in OOC? The Birmingham path only makes sense for cross-country services, but the intervals between cross-country stops, in the heart of dense industrial England, are not such as justify very high-speed alignments. The stopping pattern Scotland - NE - Leeds - Sheffield - Derby - Birmingham - Bristol is the XC core, and whilst HSUK can speed up every leg (sensibly), HS2 can't improve through routeings for Leeds - Sheffield - Birmingham. The OOC stop also makes no sense for minimising Anglo-Scottish journey times, given the previous discussions about substituting away flights by beating a 3 hr threshold.