LOL-whatever you say. He just got a SB ring two short years after leaving Dallas. The Philly OC from the previous year got canned with largely the same unit when the offense was going nowhere.
OC’s call two different plays on pretty much every down. The QB gets a chance to look at the opposing defense and check into which play seems to fit best. It’s on both individuals, but the QB gets a massive say in which play is actually run (before, during, and after games). It’s always been and always will be more about the Jimmies and Joes than the X’s and O’s.
All of the “best” coaches look like geniuses with elite talent. Tom Brady proved who was more necessary when he left NE, and had his success with TB while NE steadily declined. KM is no different-he’s taking the job with the biggest paycheck (if it doesn’t work out-he will go be the OC with some other team). Andy Reid never won a SB till Mahomes. Bill Walsh with Montana. Lots of others.