Pryor is a very mobile QB, given the Raiders limitations in the passing game with the WR's they have, no running game, I would expect a mobile QB to create more opportunities than a pure pocket passer who is no threat to run. Please remember, in regards to Pryor's play, the sample size is pretty darn small and the net result was still a loss. The Chargers also had limited game film on Pryor.
The Raiders had problems on offense in 2012, Carson was not the only reason why. I think we both agree that he needs to play better, we disagree on whether he can or not.