It's code for...
First = Don't give a toss about passenger comfort or safety critical staff been removed from trains (IEP can run DOO without a guard during "disruption") and doing on the cheap whilst damaging morale and revenue
Virgin = Enhancing service and keeping safety critical staff onboard
Except, of course, that in reality, it isn't Virgin at all. If Sir Brian owns 90 per cent of East Coast, he calls the shots, not Sir Richard. And First is running a direct award franchise, not one won in an open competition, so DfT's attitude, expectations and demands on First are likely to be different - such as facing down the RMT on DOO for IEP. Sir Brian might just like avoiding a confrontation with the RMT for the time being and letting FGW take the heat. He probably still carries the scars of SWT's attempt to introduce DOO in 1998.
IEP is equipped to run DOO any time you like. And how is it going to damage revenue? I've seen many arguments advanced here but that's a new one and seems highly unlikely given the trends in use of the railways, whoever is responsible for opening and closing train doors.
And it is a lot easier to give EC maintenance staff guarantees about the future when Hitachi is going to take on Craigentinny (which looks likely to also have work on Scotrail HSTs and the AT200 emus), Bounds Green and Ferme Park depots - with Doncaster being the only new build site - so the staff will be covered by TUPE. Whereas in GW-land all the IEP depots will be new, or reactivated (North Pole), bar whatever AT300 work goes to Laira.
The initial GW batch of IEPs is very firmly a DfT-specified train, probably just to prove that after so many years of faffing around, the civil servants could actually deliver something, whereas the AT300 is clearly more First Group's baby, so there probably is more room for manoeuvre and considering what sort of catering is appropriate on services where the average journey time is going to be a fair bit longer than on 800/801-served GW routes, a factor which may also have influenced DfT"s less dictatorial approach on the idea of buffets on EC 800/801 sets.
As for the idea Virgin is enhancing service, that one will have a lot of passengers on both EC and WC services rolling in the aisles. I doubt those who up to now have been using railcard discounted off-peak tickets on peak West Coast trains feel that their service is being enhanced as of September 6. Nor those who used to be in EC's rewards scheme.