Michigan does have a pretty strong case. They have a better case than Washington does. You gotta play good teams, and teams that don't should be punished for it. The top of the B1G has done that. OSU played Oklahoma, Michigan played Colorado, Wisconsin played LSU... the only team that didn't schedule a quality non-conference opponent is Penn State. Their rise to the B1G championship game is really quite flukey.
Really that's what the conversation should be about- not about if Wisconsin/Penn St. gets bumped by Washington, but if Michigan should bump Clemson/Washington.