It's very simple. Harbaugh inherited a staff of 60+ year old coaches that were ancient in their schemes and philosophies. He then fired them all and brought in the young coaches that related well to todays players as well as knew and coach the modern day game of football and brighter minds and could really develop players. Mike McDonald, then Jesse Minter, Sherrone Moore, Kirk Campbell, etc... They also brought in the Baltimore Ravens defense. And that turned the tide 3-4 years ago. And Michigan's coaching staff has been the best staff in the country once Harbaugh made the changes. Developed the best OL + DL in the country. Developed the most physical team in the country. Developed one of the best defenses in the country.
Michigan = physical - OL/DL University.
osu= soft - wr university.
CASE CLOSED!!