My wife is an occupational therapist, and she told me to stay away from Ben Sheets this year. She also said Mark Prior is a hypochondriac. I didn't even tell her the player names, I just summarized their injury history and asked her opinion. In fact, she barely knows any players (Torii Hunter, Joe Mauer & Johan Santana are the only exceptions).
I'd say she was 2-for-2 on those calls. People in health care may or may not know baseball, but they know the human body and they know about injuries, recovery, etc.