Of the course the main reason is BA is a dumbfuck.
I agree wholeheartedly that BA is that. However, I'm somewhat glad that he called the game the way he did the other day. It was conservative as hell, no doubt, but the Steelers D was virtually unstoppable. I'm sure that if we'd lost, I'd be singing a different tune. But, had we lost because he decided to let a rusty-ass Batch or rookie-like Dixon sling it around against a stout D that was playing pretty well in its own right, I'd be even more pissed.
"Slinging it around" and calling a pass play any time but 3rd down are two completely things. Nobody is suggesting Arians go Tommy Gun style with Batch, but when the opposition knows what's coming on each and every play, the O has no chance of accomplishing anything.