I'm sure you know the answer to that already...golf pro's are allowed to warm up, but not on the tournament course, its the same logic as snooker pro's being allowed to warm up on the practice tables and in all other Matchroom events pool pro's being able to warm up on the practice tables.
My point was that this approach is not unprecedented, I'm not trying to defend it (other than not allowing practice on the match tables themselves whilst matches are in progress as that is standard practice for seemingly all sports).
I'm simply saying that where there is a shortage of space (that's everywhere in the UK and some European venues too I suspect), this approach is used, it's far from ideal, but it keeps costs down.
I would of course hope that it gets rectified for future years as I feel particularly bad for the amateur players who will find it harder to produce their best from a cold start, but also for TV you want everyone at the top of their game (that said I don't think we were starved of quality so perhaps it doesn't affect the top guys that much)!