He's a very good pass blocker. Let's not get it twisted. Yes he has some issues sometimes with speed rushers who can bend the corner. But consider, most tackles do. Personally I think he's worth keeping. Initially I had questions about his feet, which I still think suck but he's so damn long and strong, and a good technician to boot, that it hardly ever matters.
I also don't think Andy's trying to turn Pat into Payton Manning but for his long term success he does need to learn to play in the pocket better and I think we're watching that maturation process this year. He already has done much better at taking what the defense is giving.