3. As another old duffer I feel the crucial moment came in 1987 with the demise of BCal. If at that moment the Government had said to Sir Richard--- OK you can have Manchester and Gatwick long distance, BA is getting Heathrow-- subsequent history may have been different.
BCAL ended because of a failure of government regulation. The much flawed "second force" idea was to create a large independent carrier to compete with state owned BEA and BOAC. So far so good.
Unfortunately, and this is the flaw, this "second force" carrier was denied access to LHR, resulting in very uneven competition. Consequently, BCal was unable to take advantage of substantial numbers of premium pax and the extensive connectivity available at LHR.
What should have been done, obviously, was more terminal and rwy capacity at LHR to accomodate the "second force", but that is a whole different subject for a different forum.
BUA suffered a similar fate and was bought by BCal, which in turn failed and was bought by BA (which gave it a base at LGW).
VS did manage a shift to LHR and survived and prospered, if it had been confined to LGW and MAN without access to LHR, history would probably
not have been any different.