Also if you look at their faces, Sonnen was taking the brunt of the damage via elbows from Anderson being the bottom. How many times did he pass Anderson's guard?
Sonnen in affect out wrestled him but never out grappled him if that makes sense. He went from full to half guard about 5 times. Never passed IIRC. Never maintained side control.
Don't get me wrong, Sonnen won that fight 4.8 rounds but his damage was minimal and Anderson did not look like he had an explosion.