The timings I put together were based on existing timetables which means the trains in user are 350s, 390s or equivalents - so, no, you're not likely to find improved speed on that basis, because it's already what is achievable.
Improved speed as in 110mph is faster than 75mph. I am not attempting to increase line speed run faster trains.
Off-topic I know, but what lines west of Weymouth are these? If you mean Bournemouth - Weymouth, that's east of Weymouth and it was electrified 33 years ago.
Yes the former L&SWR line east of Weymouth to Bournemouth was electrified in 1988. This was of course where the 442s originally came from. None of the former GWR lines west of Weymouth, to Penzance etc, which cannot be reached directly from Weymouth without reversing somewhere, are electrified. In fact no lines west of Weymouth are electrified. I said “west of Weymouth” because Weymouth is the western extent of electrification.
Bear in mind there is an argument that 75mph freight are hindered by stoppers, there is definitely a strong case in places that the mindset of the passenger going first is wrong. Factor in that you have to plan on green aspects, you really don't want freight on yellows as passenger trains can cope with that better.
Take for example a Class 4 from Milton Keynes to Watford, a clean time is 33 minutes, an equivalent LNWR stopper does that in 39 minutes, and that doesn't include Apsley or Kings Langley as they are covered by the Trings.
So I take it this disproves my hypothesis that a 110mph class 350 isn’t able to keep up with a 75mph freight path while stopping at every station.
BINGO!! Not only ‘yet another use for the class 442’ but even converting it to bi-mode (such a resounding success with the 769), using a class 87 for the overhead bits (I’m assuming repatriating some of the 21 from Bulgaria) and even giving it a made up classification.
The use of Bulgarian Class 87s with Hypothetical Class 792s made from Class 442s fitted with Diesel engines is a very interesting proposal, but not at all a serious one. There are a huge number of problems, not least that the 442s are only 100mph units, not the required 110mph.
The Class 769s have succeeded in further degrading the service to Southport, with most Southport services now either cancelled throughout, or cancelled only between Southport and either Wigan or Bolton, leaving Southport with only an hourly or 2 hourly 2 car DMU to Manchester. (Because enough services have been cancelled in a row that there has been a 2 hour wait for the next service that was running)
Oxenholme and Penrith already fulfil that role.
The reason drivers, including me, stop at Tebay M6 services is to have a break (comfort and more) and a bite to eat, all of which can be done on the train without it having to stop; Certainly not to visit Tebay itself. Neither service station is actually in Tebay anyway.
Tebay would of course also serve as the junction for the line to Darlington, via Barnard Castle, where you can alight for an eye test and which would be heavily used by east-west freight.