Are the hours that trainees receive at the college enough?
When you take away instructor "how about doing it this way" and they f*** up (when they've seen the exercise god knows how many times) which means you lose the plot elsewhere instead of being left to your own devices, the poor bas**** in the other seat also being told the same thing who then infringes in your airspace (or you in theirs), therefore cocking up the whole run - you've got to take away a few hours.
I know that many situations need to be demonstated to students, but the amount of valid controllers that visit the college that say " well, that wouldn't happen in real life" or "you wouldn't get traffic like that" etc etc must be a lot.
A good example (and we all know that A.340's are crap), but I observed an A.340 out of frankfurt JUST clawing through FL180 50 miles west of LHR!!! Just to prove the point that A.340's are slow climbers!!!
And how many ex students would say that its not really the ATC thats hard, its knowing what each instructor likes and dislikes that gets you through.