On the subject of electrification (or lack of it) at the extremities. I remind that the Great Western Main Line will quite soon have something in common with the East Coast Main Line. Once the infills suggested/hoped-for happen on the Cross Country core (Sheffield-ECML, Brminham-Derby then Bromsgrove-Bristol) the CC/XC route will also have something in common with the first two routes.
I have often thought that a Bi-mode does not need to be that fast on diesel as, if it was important, the relevant parts of the route would justify electrification anyway. Well it makes sense IF only it was a fair world !. It also occurs to me that as the core of Cross Country is overcrowded it is tempting to treat services beyond Edinburgh or Plymouth as separate connections. A bit simplistic but I think it needs thinking about. The option I am thinking of is that the existing Voyagers could spend more time at the extremities with a Pure electric train for the cores. If its worth keeping through services then Project Thor could be resurrected for the Voyagers to make them bi-mode AND then new pure electric trains provided on the more frequent core. I think building more and more bi-modes is a bit wasteful when the Voyagers are available soon. Otherwise I worry that the Voyagers are not really suitable on some of the alternative routes suggested for them (as someone said earlier a 4 car Voyager has less seats than a 3 car 158). Just some excuses/brain-storming for what to do with the big intercity DMUs.
EDIT :- Class172 - you beat me to it just !. Succinctly put btw.
According to the new franchise documentation by Dec 2016 the Uckfield line is required to have 40 vehicles arriving in London between 07:00 and 09:00 exactly double what arrives there now.
So what stock will provide this service?
I wonder if that requirement would justify electrification of this island of diesel ?.