For the sake of argument, let’s assume calling pitches can be broken down into several factors, which can be taught and learned. Like most other tasks involving different factors, there will be some more important than others, and I’d really like to see if they can be identified.
From what I can find out, the most important reason catchers and pitchers use signals between them, is to make sure both understand what pitch is coming so the catcher has the opportunity to best be able to catch the ball or at least not allow it to get so far away as to allow runner(s) to advance. In that same vein, many times fielders check to see what pitch is being called in order to get a jump on where the ball might be hit.
However there are other reasons to call pitches. A main one is to try to try to take advantage of the batter to benefit the defense. In some cases the batter’s tendencies are known, such as a pull hitter or being very aggressive. Pitching a pull hitter away or an aggressive hitter junk can often lead to an outcome benefitting the defense.
Unfortunately, even with loads of knowledge about the hitter, it still remains for the pitcher to execute the pitch, including throwing the pitch “properly” and putting it in the desired location for the best anticipated outcome. But even if the data about the hitter is available and correct and the pitcher is able to perfectly execute the called pitch, there’s still one more thing to consider. The hitter. There’s no guarantee the hitter will respond the way expected, and even if he does, the most minor things could throw everything else in the trash.
With all the possible permutations of how an event could take place, what is the “real” likelihood a given pitch call will turn out exactly as planned? The likelihood is probably very small, but a great thing about baseball is, there are so many pitches thrown, even a very low likelihood will produce a large number of desired outcomes, and that small number can easily be the difference between winning and losing.
But does the number of desired outcomes offset the number of undesired outcomes due to poor or misinterpreted information about the batter, some mistake by the pitcher in execution of the pitch, some unexpected response by the batter, or even just an “unlucky” bounce?
I’m not at all saying calling pitches other than for the P and C to be on the same page is a worthless endeavor. But I am wondering just how much having an experienced person sending signals in from the bench improves the chances of an outcome that’s beneficial to the team on defense.
Here’s an article written by Brent Mayne, a 15 year veteran of the Major Leagues. Although titled [b][i]11 Reasons Little League Catchers Should Call Pitches[/i][/b], it applies equally to all levels of the game. http://bluffcityathletics.com/...uld_Call_Pitches.pdf