I've tried defending him with the same argument Zoogies. Option QB brought in to play a run-heavy option offense, and then be asked to be a drop-back passer 30-45 times a game. Not fair. It is like asking a 6'10" power forward who dunks and shoots baby hook shots to be the point guard and dish out assists....it just isn't going to happen.
But everyone pretty much puts all of the failure on his shoulders, regardless of the changes he was forced to try and make.