Your are forgetting the reason that Mike Hart was so good was because of his HeART. He was our Tebow, just without the Media hype. His presence made our team play harder, work harder. He had the undeniable will to hold on the ball and never let the first person take him down. He didn't care who was blitzing his QB, he was going to launch his 5'7 body into them and knock them on their ass. When Michigan went out and lost the first 2 games of the season, he went to the media and guanantee'd a victory over a rival, thus installing the motivation back to the team not to let him down. When a new coach try to come in Michigan's state and try to make a name for himself by beating Michigan, he calls them out and sets "little brother" straight.
These are some of the reasons why Mike Hart would be a great fit IN ANY system.
I could see Hart doing fairly well in this offense. Maybe not last year with the terrible line but I think he could do decent with a good offensive line. He wouldn't have done as well as he did under Carr's offense but he still would have been a successful back.