i think he knows it is training class.

Bart is like that. When we would go to dogtrain-he wouldn't so much as blink wrong at another dog. My trainer tried so hard to bait him into fighting(so she could see just what he was doing) and nothing. You can't correct him if he doesn't do the behavior....

He knew the place-and the people. At our class-everyone knew and had the same rules-not like at a dogpark. At dogtrain-off means off-no confusing down/go away/off. No humping means no humping, not "oh-my dog is fixed"...plus-i knew that we all has the same or similar corrections. I used lemonjuice for humping/barking. So did everyone else. If bart was doing something across the room-someone else would not hesitate to juice him-and that's how i wanted it. I scruff and flatten-so do they.

So-sure, there were lots of dogs there, but he, and the others knew they could not get away with anything-it was training class!

8 dogs playing together is a pack-especially if he knows any of them.

Plus-dogs are notorious for showing off at training class. It's like when you take your car in for making a noise, and it suddenly doesn't do it. Then you get home-and it's back.
Dogs are just like that. At least mine are, lol......

that must be his mental view. He knows in class he has to behave so he does. Of course we also use a prong in class and it took him one time on it to learn that the prong means behave, he's a whole different dog on a prong. I put it on him once, he tried to take off running to the end of his leash, I stood still, he got pronged and that was the end of that lesson for him. He learns fast LOL.