Listen, the fact of the matter is that airlines only fly from LGW because they can't fly from LHR. Look at the long list of airlines that start of at LGW and then move to LHR at the first chance. VN and GA being the most recent cases. The rest of LGW's operation is just overflow. If you told BA tomorrow that they had to stop operating from LGW they wouldn't even give it a second thought.
LTN and STN are also just overflow. EZY wanting to open a base at LHR says it all. Even the cheap seats want to get a piece of LHR.
Why does no one listen to the experts, i.e. The airlines, the people who's business it is to make money from transporting people by air. Millions of pounds being paid for slots and airlines queuing up for their chance to operate only happens at one airport in the world. It is genuinely laughable that second runways at STN or LGW are considered as options. A third runway at LHR is the right decision and is wanted by the people that matter. The sad thing is that this country has long been at the mercy of the minorities so chances are the rest of us will just give in for an easy life. Stick your head in the sand and wait for the moaning to stop whilst a once great country crumbles to insignificance.