Given he has a mild concussion, not to mention the shoulder injury, I think the coaches should strongly consider holding Forcier out of practice and this week's game, and in my mind they shouldn't just consider it, they should do it. Set an example for high school and youth coaches that concussions aren't to be treated lightly. Let Tate recover (with the side benefit that maybe a week of non-use will help his shoulder some as well) and bring him back next week for Penn State week. Michigan shouldn't need him to beat Delaware State, Robinson could use the work, but most of all, there's no reason to risk Tate's future health.
Please read the Gladwell piece linked in the mgolicious (Football, Dog Fighting, and Brain Damage). I think everyone needs to see it.