I was playing high level roller when the Michigan happened. So every butt head would go behind the net and try it. Some could get the puck up on their stick during the game.
I'm 6'2" - and this was before RVH was the thing - so while on my feet looking through the net, I'd see the dude pushing his stick down on the puck and I'd simply reach over the net and push them. Didn't take much contact to mess them up.
This was also the era where everyone was Wayne Gretzky behind the net and would pass to themselves off the flat part of the bottom of the goal like Gretzky did.