Which Tyres?

What do you expect me to do with a video?

You also need to take in consideration that the tyres they ride are vastly different, especially two factor; tubular and hand-made, those mean you can run it high and still be quite supple to ride.

Secondly, latex lose pressure quickly, so if you run em high at first, it'll likely to lose maybe 10-15psi in an all day race (anyone know how much losses?).

Thirdly, I don't think racers cared, unless they're the like of Cavendish.