Things do change, but he owns the current team. The fact that a first year HC was able to pull the team out of its funk is quite telling to me.
As for your taskmaster characterization, I'm not sure where that comes from. Inside source? McDermott seems, to me, to be someone who believes in doing things the right way (his right way). If that means he's a taskmaster then so be it. He cares about his players and that shows through.
He and Beane did not have an adequate plan at RB, many/most everyone saw this. That said, the primary reason McCoy was overworked was because of the limitations of the quarterback you and many others continue to promote.