Yakyu kid...I'd rather be safe than sorry. My son is 12 and his mechanics change like the wind. He may be solid for a couple of innings and then off track the next. I am sure most other pre-teens are the same way. I have preached to him that he only has one right arm and that he needs to take care of it. To many times people think the easy way out is TJ Surgery. I do not think I'd want to go through it. At a young age, kids bodies are still developing, changing everyday and their growth plates are still an issue. You hear different arguments on this subject but bottom line is, you have to decide what is best for the development of the kid. Is being the best 11 year old as important as being able to pitch in high school and hopefully beyond. As was stated in this post earlier..."no one will remember who you beat when you were 11."