I accept that the early parts of HS2 will be built, but I remain unconvinced about some of the other related projects.
1. A NPR/HS2 route between Liverpool & Manchester might reduce journey times by about 10-15 minutes - and be very expensive. It is the cross-Pennine journey times that need most improvement, especially Manchester to Leeds / York, and Manchester to Sheffield. Unless at least Manchester to Leeds gets a high speed line, I am doubtful of the value of NPR.
However it will also increase the number is services which can run, NPR and HS2 are about the same thing capacity. One of the criticisms of HS2 is that the argument for it has changed from speed to capacity, the problem is that just isn't true. It's always been about capacity, the speed is just that it makes it more attractive to more people.
For example there would be no point building it as a 100mph railway as everyone would carry on using the existing services.
2. Experience has shown repeatedly that passengers prefer through services to connections - even at the expense of slower journeys. With a proposed interchange station in the East Midlands (Toton, or wherever), HS2 East is unlikely to attract huge amounts of traffic between London and Derby or Nottingham - the majority are likely still to prefer the MML. Likewise, many Birmingham to Derby or Nottingham, and Derby & Nottingham to Sheffield & Leeds, passengers are likely to prefer the current through services.
This is partly true, however it does depend on the frequency.
Direct trains win when they could beat the time if a connection is missed and the price isn't much more.
However given the choice between a train taking 2 hours and one taking 3 with a frequency at the change point of 2tph (so a missed connection makes it 2.5 hours) the direct service wouldn't be more popular (yes people would still use it, but not all).
If, in addition, the direct service cost £150 whilst making a change would cost £75 there would be even fewer people using the direct service.
I'll give you an example, would you rather spend 5 hours on a Voyager between Southampton and Newcastle, or would you rather change twice (Reading and Old Oak Common, so both modern stations with lifts and staff to help) and spend most of your time on an electric train and the journey take 4 hours (at least 2tph at each change point)?
I suspect that there would be a majority that (assuming prices were similar) would opt for the faster service.
3. London to Leeds may be marginally faster by HS2 East than ECML; only Birmingham to Leeds will see substantial reductions in journey time. (And maybe also Birmingham to Sheffield)
However only if you are starting in Central London, for some areas of London getting to Old Oak Common would be faster.
However even that misses the point, HS2 doesn't need everyone to use it over the existing route. In fact for those who aren't going end to end the fact that some carry on using the existing route means that they could have a better frequency than would be the case.
For instance if some still use it, there'll be a desire to not to stop at too many extra stations, so whilst a journey may show by (say) up to 9 minutes (2 or 3 extra stops) it is unlikely to slow by between that and up to 30 minutes (4 to 9 extra stops). However if there were to be assumed to be no end to end passengers than significant extra stops would be added.
4. HS2 avoids some large cities, notably Coventry & Wolverhampton. I predict that many passengers will continue to prefer existing conventional services, rather than face the inconvenience of changing stations in Birmingham.
Indeed, Coventry is likely to see slightly slower services (i.e. 1 or 2 extra stops added), however whilst that would add up to 6 minutes to the journey time for navy there would also be quite a few for whom it makes it easier to get by train to other places.
As an example, after East West Rail being fully open, a stop at Bletchley would make rail travel to Bedford or Cambridge easier to do. It would also make rail travel to Oxford more reliable as there would be a fairly easy alternative route.
5. Just how much will existing services on WCML, MML, ECML change if a full HS2 & HS2 East programme is completed ? Not everybody wishes to travel to or from London, Birmingham, Manchester or Leeds. There will be much political flak if attempts are made to withdraw (or slow down) many of the existing services.
Probably the changes wouldn't be as bad as many fear. Let's take Coventry as an example, the fact that in 2019 it had about 8 million passengers using it would likely mean that it keeps a decent level of service to London.
In comparison, whilst much closer to London passenger numbers are much smaller, Hook (0.8 million passengers) sees 4tph in the morning peak and 2tph off peak towards London. In the morning peak the trains call at 4 or 5 other stations before running fast to London. With the 3 other stations which aren't Working (which sees other services as well), total passenger numbers only equal about 8 million.
3tph all day may be reduced, however I'd be surprised if it saw less than 2tph and during the peaks it may even see an increase. Especially if the proposed from the North through the Trent Valley Nuneaton, Coventry and on to London service comes about.
6. Although there are probably too many vested interests to have allowed it to happen, a much easier - and cheaper way of increasing capacity would have been to abolish first class. In a typical Pendolino, they could have got an almost instant increase of at least 20-30% in the numbers of standard class seats, more than enough to cater for many years of anticipated (pre-Covid) growth.
Whilst it's possible to add 20-30% to the first class coaches, you're not going to get a 20-30% increase across the whole train.
The 11 coach trains have 589 seats whilst the 9 coach trains have 469 seats. To see a 10% increase would require and extra 59 seats added to the 145 first class seats (+1 for every 2.5 seats) to 47 seats added to the 99 first class seats (+1 for every 2.1 seats), which might be possible, but certainly not double that number of extra seats.
Wow would, however, gain 30% on the 9 coach trains if you did away with first class and lengthened then to 9 coaches. However that would only be on 40% of the fleet, the other 60% may gain 10%, giving a total fleet uplift of 18%.
HS2 gives a per service up lift in capacity of between 86% and 134%.
If we hadn't been planning to build HS2 in 2009, chances are it would have been planned to have happened within a few years of that due to seeing year on year growth of around 4%.
Tinkering with train capacity we could have eeked out a few more years but the need for a new line would have become inevitable.