The thing with Foles is that he looks the part. He could adjust pre-snap, and he doesn't look or sound like a clueless nerd like Tribusky. He has the hardware and a superbowl MVP under his belt. All that is going to inspire more confidence in his teammates. He's got the fire and the passion and in a violent and passionate game, that's important.
He's also faced extremely tough defenses whereas Mitch went up against some of the worst defenses. I expect Foles' numbers to start looking better over the next 3-4 games.