It has? I'd like to see the source of this, as the few articles I've read that claim to prove this were so specious and riddled with flawed logic it's laughable. But you may be referring to a different study than the ones I've seen, in which case I'd be interested in seeing them. The best info I'm aware of (and I'm not aware of much, to be honest; I'm not as well versed in baseball statistics as some others here) comes from Baseball Between the Numbers. I unfortunately don't have a link, because I read it in a book, but the authors are all BP guys, so I'm sure their info is on the web somewhere. I didn't consider the logic of the analysis too deeply, but it seemed sound to me at first. If not, I'd love to hear why.