As stated, it comes down to proper mechanics [and also if a youngster's anantomy at the time will withstand the stress]. I think the main point is this: Why jeopardize a kid's health and future?? So you can win some mythical state championship that are a dime a dozen? How many HS or collge coaches give a rat's behind what your record or BA was when you were 12?? The problem with the article is that most of the guys out there coaching think they are smarter than the "real experts" and will justify it one way or another in order that they can win. Every kid is different [and that is also one of the justifications guys will use - it doesn't apply to my kid], but Junior learned a breaking ball froma former Atlantic -10 pitcher of the year [guy is still in his 20s] and worked on it more with a current AA pitching coach - he has pitched since he was 9, and the ONLY time he had a sore arm/elbow was after pitching for the first time at 60' [pitched at 50' for 2 yrs prior] on a cold night and going 5 innings [had I been at that game he would have been out before then]- that was 4 years ago. He thanks me now for not caving in to the pressure [and his begging] to throw one sooner - all the "studs" that were striking out mucho batters with their big sloppy curve balls that no 12 YO could hit are no longer playing basebal, since by the time they were 13-14 - their arms were like spaghetti. The short versino is that there are no rewards at 10-13 that justify the risk.