Dennis,
I've had near-misses with the Tour de France before, but from my experience with meeting other tours, watching is very dull if you don't know what's happening, plus they tend to block routes for whole days. (The only fun part is actually watching the spectators, IMO.)
But anyway, I couldn't have gotten there earlier by bicycle.

Tattie?
I would expect the main problem with Edingburgh to be: Getting there. The only times I've been in Scotland it was around Berwick upon Tweed. Looking at the map I got the impression cycling from there to Edingburgh was going to be rather challenging for me. But if I would have nothing better to do, I could try, of course.
Then again, having only one camping site in the vicinity of the city might pose a problem as well.
But thanks for the suggestion.

Bye
                                                                Mysha