I pitched for Arizona. I was drafted and then had an career ending accident skiing. I have coached at every level other than MLB/MiLB. Still do so today. I also founded the largest "program" in the midwest. I know James Andrews personally and am very involved in the AMSI where science of the game is very unveiling nowadays. Everyone has their opinion, you are welcome to yours but I wonder how many (true numbers) young players you have first hand knowledge of, as in true involvement, to have such a firm opinion???
I know many pitchers that have been in the show, or still are, and each and every one of them knows they are different than the next in minor ways mostly. Then again there are those few that go against the grain and have success too. That does not mean that is the norm though. For every 1 kid you suggest to develop a curve at such a young age that may get away with it without injury, just how many do you think it will harm? Andrews is THE top Tommy John surgeon and I am sure you have not been to his house and had the discussions I have detailing how the numbers for younger surgeries have grown 400% in the last 6 years. I guess the whole AMSI is wrong spending money in research to find the reasons for such increase. The number one reason IS developing deception pitches, mainly a curve and slider, at too young of an age. It is recommended to not develop these until your growth spurts ( growth plates) fuse together which mostly means 15/16 years. That is when you start "developing it".
Bum, you sound like one of those dads who started his kid out really young, wanting to be stand out at 9 in league ball. I am uncertain what that proves at that time but you apparently have gotten away with it without injury. That does NOT make you right. I am happy for your son that he is injury free but will turn a blind eye and deaf ear to your reasoning going forward.