Hehehe oh I so know what you mean...
I remember after the first few days of using cloth, one of the nursery staff asked me how long the nappies usually last - I said well 3-5hours depending on etc etc - she replied I wonder why she was soaked thru within 10mins, I asked if she'd put a wrap on at which point she blushed, made her excuses and ran off laughing to herself!!
I quite often find that they put her WN wraps on back to front, so much so that I've actually written "back" and "front" on the inside of one of them!!!
I think for ppl who're used to dealing with disposables, and for all my moans, our nursery actually do really well... And like you say, there's never the time to hang around and explain!!