I'd be interested in seeing Chip's stuff from other stops to see if he avoided the middle intermediate stuff like Gus does. Year ago, may have been when he was OC here, I remember Gus talking about the middle of the field being the most dangerous place to throw the ball. Tipped passes, lurking LB's hiding in zones, harder to read what's going on there for college QB's. The outside is easier, simpler. Deep ball goes wrong it's basically a nice punt. I think this is just an example of risk-averse Gus. It's an area he won't target often or at all if he can avoid it because he views it as not worth the risk associated.
My kingdom for some seam routes though.