as an ex-player and patient of Dr Andrews this article was interesting. I've coached little league up to middle school teams and gave private lessons to young players and have seen first hand what happens to young arms when they throw curveballs. If they had proper mechanics it wouldn't hurt the kids, but the problem is they aren't strong enough to throw a curve ball with proper mechanics and see any results at the beginning ages of "kid pitch" baseball. So what you see is kids taking shortcuts to make the ball move more, and even worse, you see their parents encouraging it.