Don't think there's anything wrong at him having a bit of a laugh when they were 2-0 up, I suppose there's a bit of character about him - however, his main problem is he's really shite.
He must be in the bottom few keepers in the prem in terms of quality. The Huddersfield one is pretty shit, Begovic is criminal too, and Dubravka's had a few howlers recently, there's also the one at Fulham who deserves a mention. There's probably a few better keepers knocking around the championship too.