Tell me what pro team does not incorporate a throwing program into the pitchers training? It is not an option, the only option is how far you feel comfortable with throwing. Bullpens are done once between a starters start, nothing replaces a throwing program.
Do you think that youth programs are going to say that 8,9,10 year olds should pitch? When son was young they had coach pitch, you will not find that as often these days, I am sorry we began him at 8, because nothing counts, relly counts until you are loooking for that college schoarship or trying to get ahead in teh organization that drafted you and your shoulder or elbow blew out.
As far as stretching I did not say it was bad, I said over stretching is, once you stretch out to the max, the reversal is a long and sometimes fruitless process. Healthy active very young bodies don't need stretching, seems to me that your son has some issues, if the course of seeing doctors is to correct a problem that has nothing to do what someone else should do.
Sounds like your son is throwing a slurve, that's not a true curve and not a true slider, there is a seperate distinction in both, find out. Don't go touting your son throws CB's when he is not throwing a curveball. Most young players throw the slurve, it's safer.
If he continues to throw with his ARM, good luck.
I don't always agree with YB, but what he says about biological age makes sense, in relation to what I stated aobut the growth plates.
I am not inpressed with complete no game hitters, or win/loss records or ERA's for young pitchers, it means nothing in the long run. Tell us when he's past HS, it has a lot more meaning. Usually you will find those typs of players, you know the harder throwing ones getting everyone out, don't go very far.