2004: Dislocated his left shoulder in fall drills and re-injured it several times during the season, requiring surgery in January 2005.
2005: Bothered all season by a chronic right high ankle sprain that eventually forced him to miss the Baylor game (10/22) and more than two quarters of action in each of the Kansas State (10/01), Texas (10/08) and Kansas (10/15) contests.
2006: Suffered a left collarbone fracture vs. Iowa State (10/14), sitting out the next seven contests vs. Colorado, Missouri, Texas A&M, Texas Tech, Baylor, Oklahoma State and Nebraska.
http://cbs.sportsline.com/nfl/players/draft/517568
******************************************
I dunno, but does that looks like a big red flag to you ?
AD will see more hits, and definitely more big hits in an NFL preseason than
what he saw in a full season in the mediorce Big 12.