Sorry if I may have seemed overly negative...it's a real challenge to fit 13,000 vehicles into such a remote location and get them out again as well. Perhaps its a shame to overlook the fact that 13,000 vehicles and passengers made the trip in the first place...plus those who went by coach and rail. Scotrail certainly seem to have a very good arrangement in place.
My first memory of RAF Leuchars was as an 8 year old some time around 1980 or thereabouts and it was a double-decker bus there and back....I think it was a queue to get out then as well....but we're British, after all! I've been back to Leuchars since many times, as a youngster, in the service (including arranging a visit for my brother who joined up) and after leaving the service.
Park and ride schemes tend to work well and are actually popular in quite a few places (Oxford, outskirts of Edinburgh) but it is difficult to prise people out of their cars for more ad-hoc arrangements and requires plenty of carrot as well as stick. I will try it next year, would have gone this year but was visiting the in-laws.