More flights to JFK & LAX etc. will help DL & VS win corporate contracts and more flights to DL hubs at DTW and ATL will multiply the connections DL & VS can offer to/from LHR.

A point made repeatedly by WW (who clearly rates Richard Anderson at Delta) is that it's easier to make commercial decisions when competitors are acting rationally, and I doubt BA is surprised by this. The AA/BA joint-venture is in a much greater state of maturity and will continue to gain network strength when more 787 routes are launched.

Also, when you add the loss of Cape Town, Vancouver, Mumbai and Tokyo to suspensions to Accra, Nairobi and Sydney the scaling back of the VS network is significant. And some of those routes (Tokyo for example) were hard fought for by VS. It would certainly have been interesting to have been a fly on the wall in some of VS board meetings in recent months.

It's by no means a given but consider how different things could have been if, instead of protesting against the AA/BA joint-venture, VS had secured DL as a shareholder in 2009 and DL had been willing to bank-roll the purchase of bmi from LH.