Want a sign that Michigan is probably not coming for Brad Bates this time around? They are letting their interim Athletic Director make the call on Brady Hoke's future. This reinforces speculation that their interim AD Jim Hackett will move into the role as a full-time replacement for Dave Brandon. If that happens, Brad Bates won't be returning to his Alma mater now. Even if the school decides to find a different AD, I don't think Bates nor any other AD from a Big Five conference would take the job.
An Athletic Director's job is multifaceted. However, there is one aspect that is very public: hiring and firing coaches. When Bates was hired by BC it was assumed that he would fire Spaz, but he was hired at a time so that he could evaluate the situation himself and have enough time to find a replacement. Any AD that comes to Michigan is going to have to live with the decisions Hackett makes in the next few days. Football -- especially at Michigan -- drives the bus, so everything the new AD would try to do would be hampered by a decision an interim made. That is unworkable for most folks. I think it would be especially unworkable for a methodical guy like Bates.
I don't expect Bates to be a BC lifer. He still could end up at Michigan in a few years, but now is not the time.