I have heard of some ATPL students having the keys for the mags pulled on them during PFL's. But I have cocked them up on a few occasions (during my PPL) and think it's a bit sketchy to do that to someone
I would be surprised if that was the case at any of the integrated FTO's - dangerous instructional practice. The twins have mag switches in any event - not operated with a key, & PFL's are not practice during MECPL training (unless you identify the failed engine incorrectly
).
My previous comment regarding 'good training' was intended as a little subtle humour - clearly I need more practice.