Yeah, but what will run the Gerrards X stoppers ?? they are based on fast accelerating stock. If they get more loco hauled in, that will only release 168s, and they cant get up to speed quickly for toffee....
Chiltern will need the 172's for evergreen 3 as they need a very quick train to be able to run the timetable from Marylebone to Brum without the stoppers slowing the fast services so it would be poinless they use anything else!