Arians apologists cite statistics. With BA at the helm, we'll have a 3,000 (possibly 4,000) yard passer, 1,000 yard rusher, and 2 1,000 yard receivers. Anyone who is OC of a team with those stats should be safe.
What about the yards left out on the field?
Looking at the talent, we SHOULD have a 4,000 passer, 1,000 yard rusher, and 2 1,000 yard receivers. In those four players are three first round picks, a future HOF, 2 Super Bowl MVP's, and one of only a handful of QB's to win multiple SB rings.
But what about the yards left out on the field? With competent coordinator, these stats aren't gaudy, but habitual. With a better coordinator, we don't see QB keepers on 3rd and 6 in a home playoff game. We don't see a toss sweep to Mewelde Moore on the brink of FG range in OT on the road. We don't see empty sets on the road (Philly, Cleveland) on 3rd and short when you have a porous O-Line and QB whose weakness is his hesitancy on the quick throws.
Last point: How many times this year did the offense have the ball with the chance to win the game, and fail? Last drive against Cinci (I think it was 4 straight incompletions, all throws with heavy pressure on Ben), twice against KC, scoring with 1:50+ against Oakland with a chance to run the clock down, and pissing away time in Cleveland when you needed two scores to win the game and getting the ball back with about 6 minutes to go and playing it as the last drive of the game and leaving yourself no room for error. Screw the stats. I want a competent OC who understands the team we have, and who doesn't win only because his players bail him out.
It's not asking too much to get an OC who gets more from the players than they think they have. It's ridiculous to keep a coach whose players make him look better than he is.