It turns out that really my son was suffering and punishing him for his behavior wasn't helping him. He was miserable, we were miserable, and nothing was improving. Only once we understood what we dealing with and changed away from thinking of his behavior as misbehaving did we start to make progress. And now he's a wonderful well behaved kid.
I think it's really important for kids with actual issues to be diagnosed. For every kid were diagnosis might possibly permit parents to make excuses for their children, I suspect there are 10 more with frustrated parents doing all the wrong things.
It may seem that way on the outside, but that's only because you haven't lived on the inside. It's about understanding where these behaviors come from so that you and your child are better equipped to deal with them.