One of the biggest pro-R3 hints from the government was at exactly this moment, when chancellor Osborne said this and the cameras were by now on Boris (due to him having been mentioned two sentences earlier - and I bet Osborne had his eye on the cameraman to ensure he had swung to have him in shot), that there was a huge laugh and snicker from all his Conservative colleagues sat around, all at his expense.
Regarding prospects for The Girlie, Justine Greening, former anti-R3 Secretary for Transport for about five minutes once, if you recall, you may have noticed that there she was, best dress on, desperately squished up against her ministerial colleagues on the front bench to try and get into peripheral camera shot when it was on Osborne. No, she's not going to give up all that for any principle. And Putney, which she represents, is not under the R3 approach at all.