Here's another really good read
on the topic of arm mechanics, and the war between doctors/biomechanic-specialists/science and traditionalists.
"The picture that emerges is of baseball at war with itself over the health of its arms. In one corner stands a cottage industry of scientists and biomechanics-promoting coaches who study motion for a living and have determined, through high-speed video analysis, that the sport's ignorance of arm-saving science is a shameful oversight. In the other is major league baseball, which, with rare and fleeting exceptions, clings to a deep-rooted tradition..."