If you think that it is unrealistic for a program like Michigan to be very good to excellent in 2-3 years, then you clearly have no idea of what UM brings to the table.
Alabama, UF, OSU, Auburn, Oklahoma, Nebraska...these are just a few teams who became elite within short time frame after the hiring of a new coach.
People act UM is the post-Millen Lions. They were not.
spoiler alert: i linked this