I don’t think Sonnen’s a one-dimensional wrestler like many folks make him out to be. He has fast hands and a weird, jerky head movement. And it showed when he dropped Silva twice in their first fight.
Even his wrestling isn’t what generic NCAA guys like Ryan Bader, Mark Munoz, etc. employ. First, Chael is more speed-based than power-based. Second, Chael positions his head in a weird way on his double legs. I believe Mohammad Lawal commented on this once.
As for Chael’s lackluster performance against Bisping, I think many people overlook Bisping’s takedown defence. The guy held Rashad Evans to a split decision back when he was a light heavyweight!