Jim Harbaugh likes to run a run-heavy version of the West Coast offense, and some elements of the spread thrown in. I'm somewhat surprised that someone like Peters couldn't beat out Patterson or McCaffery, especially considering that his high school offensive scheme wasn't too different than that which is currently implemented.
It's not a very complex offense, and if he couldn't master that offense with all of his talents, I highly doubt he would have been able to thrive in Brian Kelly's hybrid pro-style / spread offense that has a pretty steep learning curve.
I'm also rather surprised that Jim Harbaugh hasn't been able to develop any quarterbacks at Michigan (Wilton Speight arguably being the sole exception) in his entire time there, instead relying on transfers as stopgap measures.
If anything, I'm glad that we got Ian Book that year instead...
Link: https://247sports.com/Recruitment/Brandon-Peters-33735/RecruitInterests/