Rollerman ,
You must do whatever you think is in the best interset of your son , and if you felt comfortable starting him at 7 years of age was in his best interest , that what you needed to do . I am very happy that he stayed healthy over his career . I still feel very comfortable about a general starting point being 14 years of age , but like yours , this is just my opinion . I do believe in doing other things such as agility , flexibilty , bodyweight weight-training , form running , hand-eye coordination training , and anything else that will help him become a better athlete , and that he enjoys doing ,
Best Wishes ,
Kerry