On various message boards, I've seen two widely divergent strategies for how to use Shane Morris in 2013.
One school of thought is that his potential fifth year has far more value than occasional spot duty as a freshman. Therefore, it would be better to hold him out of action unless they're forced to play him — i.e., Gardner is out with the game on the line, and Brian Cleary can't get it done.
The other school of thought, is that as starting QBs seldom make it through a full season without being knocked out of a game (or games), the coaches ought to assume that'll happen, and therefore get Morris into the action as soon as possible. This strategy assumes that Cleary could never play acceptably against a serious opponent, and that a prepared Morris is bound to be better.
For example, suppose Michigan is up on Central Michigan 34-6 after 3 quarters. If they're pursuing the first strategy, the coaches would play Brian Cleary for the 4th. If they're pursuing the second, they'd play Morris, or perhaps a mixture of the two.
Devin Gardner is the textbook example of what can happen when you burn a promising QB's redshirt. He saw only meaningless action as a true freshman, but fortunately was able to get that year of eligibility back, due to a back injury. Of course, Michigan had Tate Forcier that year, so they never really had to use Gardner; burning his redshirt was elective.
The real question, then, is whether you think of burning Morris's redshirt as inevitable (therefore, you might as well burn it immediately), or possibly avoidable (therefore, you should avoid it as long as you can).