Ah, I see the the post moderation made it hard for us to follow this thread. I would watch your son closely when this school year starts if you decide not to pursue this further beforehand.
If your son is unhappy, if he continues to have trouble sitting through material he already knows, he may start to resist school more.
Your school did give you some very standard "lines" about social development. I agree that it is very important, however, we send kids to school primarily to learn, and if they aren't learning (like all the other kids are), this isn't going to work how it does for the other kids (in my opinion.)
For the record, I went through a similar situation, and eventually we did need to skip a grade, skip an additional grade in one subject and then we had to find another, more flexible school that allows you to work at your own pace.
