Oh yeah, I think Lake's reaction was, in part at least, caused by Petrie's reaction. But in Petrie's case I'd be going for the "but he started it Mum" defence. As for Lake's he's a ****** so I've got no time for him.
I saw that bit on 360, and I agree Lake's flipout may have been made worse by Petrie, but the bit that bugs me is that he keeps trying to choke him as players are dragging him off, a couple of seconds later. I'm not sure very much mitigates that. At that point, he looks totally savage and out of control. For me, he has to go for a while.