I think every kid is diffent. Most importantly, if he commits to being only a pitcher he has to be totally focused on that, and not be in the situation where he gives up other things, other baseball duties, or other sports which he may enjoy. My son is going to pitch next year at a D1 school. He pitches from the end of February to the (at least last year) begining of August. He then played football, then basketball and even now in his senior year he plays other positions on his pitching days off. He probably would have been a better pitcher if he had given up all the other sports, and concentrated all year long on pitching, but he would have been unhappy. High School only happens once, now he knows after this season it will be pitching all week long, all year long, and he is ready for that...but he was not ready at age 15, or 16 or this year at age 17....I thought maybe he should concentrate on pitching starting this year, his senior year, but I got some advice from someone who told me "they are only kids for a little while, let him play whatever he wants to play." I think his senior year, and previous years, were more enjoyable because he competed at something all year long. Too much of one thing can cause many young kids to lose interest.