I do understand most of the above but there are more than enough front end passengers who just fly across the pond in either direction and dont take connecting flights and most people in the UK fly to the US and connect to US cities.
If I was an American flying to Europe my very last choice of a connecting Flights would be via LHR its just to full and not very passenger friendly AMS,CDG and MAD are much nicer Airports.
Like you said STN had MaxJet and Eos who were doing ok until American Airlines came to bully them out, AA flight from STN were alway busy.
My point and your point regarding 3hrs drive to a International Hub - and BAA did not build the M25 is true but it should not take 3hrs to drive that distance and there are many people who drive to LHR who live all over the UK who drive past many Airports on the outskirts of London that could fill a flight to the US .
I guess I will just have to wait until next year when AirAsia may go Transatlantic
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