Knowing might make him less hard on himself. We flat out told ours when she was 6.

She knew something was "wrong" with her. She doesn't put together predetermined art projects very well and isn't really able to draw objects on command. She can't climb on the bars like her friends can. She gets tired running around at recess. She really just can't do what the other kids do. Sometimes--a lot of times--she gets in trouble for not doing the things other kids can do (i.e., getting on her backpack in a timely manner). She annoys all but the most special teachers, and she knows it.

Knowing it has a name makes her feel less badly about herself as a person.

Is it possible that she uses the label sometimes to not do something she can do or to not try at something she thinks she can't do? Probably. But I'd rather that than have her feel like a total failure.