Do people not understand that Heavyweights generally have less skill then all the other weight classes? It's not surprising that he could do that to Gane. (rare exceptions like Mir, Big Nog, Aspinall)
Periera has way better grappling D then Gane.
Jan who is a black belt in BJJ couldn't finish Alex from rear naked choke position. And this was several months ago where Periera has only improved since then.
Jon Jones has never been kicked in the leg by someone like Periera which can be a HUGE game changer and boxing offense/defense has always been the weakest part of Jones game.