That's always been sort of the way I looked at it. I think that the "disorder" called ADD isn't so much a disorder as a different way and pattern of learning that is just as natural as the so-called "traditional" manner. All through history there have been people who had trouble paying attention in class, and it wasn't until (conveniently) there was a drug available to take care of this trait to make things easier on teachers. In almost every case of ADD I know of, the tests/diagnosis was initiated by a "teacher".
When you look at the curve of learning methods and behavior, you'll find that a huge percentage of the population have this trait. I am sure that there is a nearly equal distribution of people on the other side of "normal" that have intense concentration and focus (i.e. the opposite counterpart of ADD). In addition, if ADD were a disorder, why would people with this "disorder" also by typically accompanied by above normal IQ scores?