It would appear as if you're assuming everyone will be starting their journey in London which, if I may say so, is a little presumptuous.
For me, if I want to fly to HKG then I have a choice - I can fly BA via LHR and on to HKG or else I could fly via LAX with either AA or CX. It is very unlikely that I would fly with BA in circumstances like this as flying east to HKG is illogical.
Likewise, if I am flying back to the UK then I have a choice of BA or VS with direct flights, or only BA if I fly via PHX for example.
I appreciate that BA is - by definition - a British carrier and that a large percentage of its passengers will be based in the UK but I am sure I'm not the only ex-pat on this forum
