I'm getting just a little tired of having to revisit this ground, again and again and again. Lately, every week in my Tuesday chat, at least one person asks me about some pitcher with a low ERA and a lower BABiP. As gently as I can, I explain that a .217 (or a .223, or a .235, or a whatever) BABiP simply isn't sustainable. Not for Trevor Cahill or Tim Hudson or Cy Young or Greg Maddux or anyone else. Next, the questions queue gets loaded with arguments from the same guy, and usually other guys too, that while such a BABiP might not be sustainable for most pitchers, it's sustainable for this pitcher because of X or Y or Z. These arguments -- most of which I don't post -- only become more pleading or strident as the hour moves along. It's not sustainable, and it doesn't matter who's doing the pitching. Trevor Cahill is an incredibly talented young man. I would trade my left arm for his right arm (well, most of my left arm; I need some of it to do the Jim Abbott thing). But if can consistently keep his BABiP below .250 -- let alone .220 he'll be the first since the 1970s.Rob Neyer on BABIP and Trevor Cahill. Rangers fans might recognize what he's talking about.