I don't think Benjammin was trying to suggest the drugs are useless but rather that way too many people seem to be diagnosed with ADD even if they might not have it or the symptoms are mild.
I mean, we all tend to forget and ignore stuff. People are lazy by nature and try to avoid hard work if possible (knowingly or subconsciously). My desk is pretty cluttered and I forget to pay a bill every now and then. But that doesn't mean I have ADD. It's just the kind of stuff that happens to everybody.
Now, I'm sure some people have a genuine condition that requires serious treatment. But the way things are right now half the kids are supposed to have ADD. Back when I was growing up in the 80's (heck, that's not even such a long time ago) we didn't even know it existed. I think it's way too often abused as a convenient excuse and there's the promise of an easy cure, just taking the right pill that will settle everying. But in a lot of cases, a more balanced lifestyle and taking personal responsibility would likely solve the problem for a whole lot of people whereas they pills might not.