All of the top QBs have blemishes, really only Stafford has played a clean efficient season so far. Even he has an unusually high number of passing TDs inside the 5 which is boosting that number.
Up until the last 3 games Allen really had a chance. The Dolphins game and Texans game knocked him out of realistic contention. Not really because of the stats, but because it all but eliminated the Bills chance for the #1 seed.