I was talking more of the passengers point of view, I think having both of London's biggest Airport way south of London and on the bottom side of the M25 is just wrong. I dont care if it were STN or LTN but more longhaul flights are needed north of London, On a recent flight from LHR to LAX out of the few people I talked to there was a couple from Doncaster with two young children, A lady from Keswick in Cumbria and a family of 6 from Norwich they all hated the fact that they could not use an Airport North of London, All had drove to LHR and found it very stressfull.
So all I am saying is, If the few people I talked to,12 including me, All would have chosen to fly from an Airport North of London just how many people on that one flight traveled from north of London. The demand is there, Airlines are trying to save money so why not STN or LTN ?