It makes sense that pitchers would have some control over where the ball goes.  That has been why pitching coaches have taught "pitching to contact" for years and years and years.  It makes sense especially that pitchers are more likely to induce favorable contact when they have a favorable count and are able to make guys chase pitches.

Still, there are few guys who have shown a repeatable, consistent skill for keeping their BABIP allowed numbers amazingly low.  Maybe, just maybe, Cain has been completely responsible for his low BABIP numbers.  Maybe, just maybe, Pedro Martinez was responsible for his .253 BABIP against in 2000.  If so, though, why did Pedro Martinez, one of the greatest pitchers ever, have a .344 BABIP in 1999 and .284 in 1998 - all of which were excellent pitching years for him?

There is a big difference between Voros saying "pitchers have very little, if any, control over where the batted ball goes" and saying "guys have only a limited ability to determine whether a batted ball will become a hit."  There are rockets and bleeders, and many rockets will be caught while bleeders squeak through for a hit.

As I said, I do think Cain has shown an ability to have a lower BABIP.  The sample size isn't big enough for me to say with any certainty where his BABIP numbers will settle, and even with great, great pitchers there is a lot of variation.  Zito is inarguably good at controlling BABIP, and we have 6 full years and 2 partial years as evidence.  His career BABIP is .268.  That is awesome.

But even Zito has big fluctuations:  .248 in 2003, .300 in 2004, .252 in 2005.  There are going to be variables for which we can control, such as who played defense behind him - for example, he had Tejada at SS in 2003 and Crosby in 2004, and different OFers in different years.  We can also look at where those balls went - for example, he had a 14.8% IFFB% in 2004 and 16.5% in 2005 (that helped).

BABIP helps us in certain ways.  We can look at a guy who has really outperformed his career norms and see that he has a abnormally low BABIP, and usually that regresses.  Some guys are just going to be luckier than normal.  Remember, BABIP isn't very predictable.  Even a guy with consistently low BABIP numbers like Zito can throw out a .300, while someone with normal BABIP numbers like Johan Santana (.287 career) can have a outlier like his .259 2004.

There are a lot of things at work here.  BABIP only means so much, because the number depends on the defense behind the pitcher, what kind of balls in play the pitcher is getting, etc.  ERA, adjusted for park and league, is a much much better predictor of performance.

BABIP usually is useful, though, when you see an extraordinarily low BABIP number like Cain has right now.  It is very, very unlikely, from all the information we have, that his BABIP will stay that low.  Even if Cain has a lot of control over where the ball goes, he doesn't have control over where the batter swings, how the batter swings, etc, and neither Zito nor Greg Maddux nor Roger Clemens nor Pedro Martinez nor Johan Santana nor Randy Johnson, in their very best years, has had a .242 BABIP for a full season.