It appears LHR will remain as a hub airport, but is a second London hub airport viable? The airport commission may think so.
Personally I think not, as any alliance moved to another place (LGW?) may view it as getting the short straw – both in terms of geographic location and being remote from where the real action is. Skyteam already have their own major hub within close proximity/easy access.
However the Airports Commission, who will make the ultimate recommendation, to be accepted/ignored by parliament, is hinting at a 2 hub solution. Although desirable from a cost perspective, I cannot see it developing into a hub, let alone an alliance opting to leave LHR, so is this a none starter? How could an alliance be incentivised to move?