Leaded gasoline caused violent crime? Critiques wanted.

I posted the article. First and foremost this appeases my "common sense" but the article seems to attach the strongest importance to the weakest evidence which is a pattern that the original researcher sifted through data to find a match.

One reason this is important is this: Why is it a 23 year lag? If there were another set of data that could relate the lag to ages of criminals that would be pretty great but the author leaves this open.

It seems like an excellent jumping off point but for many reading this I think they might see it as case closed which it isn't.