Par, that picture is so precious, I just want to bend down and kiss that collie schnozz of his.

That instructor spraying bitter apple sounded extreme to me too.. Unless the dog was about to take a bite out of someone, that was a rather extreme reaction and I agree with Anna that it should be left to the owner to handle it. If the owner wasn't handling it I would think the instructor should ask them to. It might be best if not all came back, it sounds like a large chaotic class, perhaps it would be better if it were a bit smaller, but maybe next time will go better.

It should be a good experience but like you said I'd be wary of the methods, because a collie especially takes a very very gentle hand in training or they can become despondant and spirit-broken. I remember how light I had to be with my boys... just a whispered "no" was enough to make Willie depressed for an hour...