Meh, Overeem hardly looked to be a 'shell' of his former self.
The Reem who fought Fabricio looked ten times worse and I'm pretty certain he was on the juice then. Overeem looked fine in the first two rounds and controlled Big Foot rather easily, despite fighting like an arrogant jackass. People are reaching... the only thing different about Overeem this last weekend was that he left his jaw five feet out. I doubt he'll do the same in future.
People who use his performance against Brock as the measuring stick probably haven't seen a lot of his fights.