Looking at what DfT have proposed as potential future electrification schemes what's currently South TPE as far, west of Doncaster is included, as is Selby-Hull but not Trafford Park - Liverpool SP.
They are also proposing:
* Chopping Liverpool-Norwich at Nottingham
* Giving Liverpool a half-hourly service to Sheffield post-North TPE electrification
* Running additional Manchester-Sheffield services.
* Changing South TPE to go to Hull after Doncaster instead of Cleethorpes.
So there will be potential for electric services between Manchester and Nottingham and Manchester and Hull via Doncaster in the future but then what'll happen with the CLC line?
Chopping Liverpool-Norwich seemed like a good idea to me. It raised a few thoughts.
I imagine these long routes are at risk of picking up delays at one end and then passing on delays to other services at the other end of the route anyway. Given how busy the railways are these days it is probably more likely to be an issue than (say) fifteen years ago. Its probably more acceptable than on an intercity route where cutting, for example, Paddington to Penzance in half at somewhere like Bristol would be a no no !. OK I find myself worrying about that happening to Cross Country and then again things like Liverpool-Norwich is a future Cross Country type service ?.
One practical problem I can see is *IF* there is not enough platform capacity at, in this case, Nottingham to handle trains arriving from Liverpool and another departing for Norwich and layovers. Obviously the other problem is passengers having to change trains. In the case of Cross Country it could be hopeless at Birmingham New Street - where capacity is already overstretched. Unless the platforms are long enough to terminate one train and then start another from the other end of the same platform. If both trains are five car Voyagers then easy but if its two 8 /10 car services then no room ?. Anyway its morally not nice to make passengers walk half the length of a platform for a "connecting" service while another group of passengers are heading in the opposite direction of course !.
I have wondered about Cross Country before as I can see there being very little infill electrification required to make Cross Country North of Birmingham 100% electric. Another case for IEP (not that I like IEP). Off topic really.
I would say Bi-Mode is not an option for non intercity (including cross country) routes. The kind of routes this thread is covering.
Generally speaking I think the railways must be looking at cases for splitting services where a large part is diesel running under the wires. Contentious perhaps but that will become more acceptable as the price of diesel goes up and the environmental issues get raised (even higher). The more important routes will survive intact as they will get electrified in full (One would hope !).