"Rupert Candy" wrote in message
...
Incidentally, why did they have to make a 'pretend Underground train'
out of a watered-down suburban train with only 2 doors per side?
Surely the future S stock would have made a much better base vehicle
for this sort of application?

Probably because the Electrostar bodyshell already meets existing safety
standards for the mainline railway, where as S stock is designed for
metro-type operation, so would need to go through acceptance procedures for
the NR system. Presumably Bombardier felt it was a lot easier (and less
risky) to get acceptance on a variant of an existing, in service design.