Viva 77 makes an interesting point about reporting level in a hold. Going back to my airfield days (yes I have been there!!) the request was to report leaving a level in the hold as the bible says that once an a/c reports leaving a level (if standard separation exists and will exist etc) then the next one up can be cleared down. It is a remarkably efficient way of ensuring that the first a/c has actually left the level he says that he has left!!
Under normal circumstances the only time I would like to know when an a/c has reached a level in the hold is if there is turbulence and the second a/c is not going to be cleard down until the first a/c is at the level.
I have also found this useful when running a hold in area control!!
PP