LHR is really about the future of BA. BA will not be able to expand with the constraints imposed by LHR's infrastructure. And when ever there is spare capacity, it always seems as if it goes to BA's competitors. LHR is not, and probably never will be, big enough to enable BA to be the airline would like to be. Its only solution is to move to somewhere else. Let the dinosaurs remain at LHR. The ideal location for anew airport would be on the north west coast of the UK, located on a through railway line or regional terminus. Run high speed trains to all points of the Britain and create an in-train check-in. Then allow LHR to come the airport it should be - a small regional one located in a pointless location or better than that, a housing estate full of people who keeping complaining about the lack of noise.
What will actually happen? Eventually (15 years?), maybe another runway will be built. But that still won't be enough - taxi and waiting times to cross active runways times between the new, third runway and parking positions will make it all but useless. By then, CDR, AMS, DUS, FRA and maybe even BRU will have left LHR in the dust.