This fangraphs article is possibly the most fascinating thing that I had read about neuroscience behind (quick) decision-making, ever.
The problem with seeing the ball out of a pitcher’s hand, obtaining some information, and translating it into reaction is that the information is usually too complex, too wrapped in uncertainty, and the amount of time available is too small. The article is probably being fair saying that how most batters cannot really describe or explain what it is that they see or how they process the information–it is not really a deliberate “analytical” process, but it is still a reaction that is both learned and “analytical” if in a slightly different sense–of having a fairly small set number of probable reactions, learned through both experience, analysis, and “intinct,” into which a batter can switch into rapidly–a set of mental shortcuts if you will. A useful analogue might be parties in politics: there are just two bins, or 4, depending on how one conceptualizes the universe: there are liberals and conservatives, Democrats and Republicans. Most politics fit into these categories (or the combination thereof). If it’s not any of these, the brain will be confused in the short term, and without an obsessive interest in figuring things out–and this kind of interest is rare in politics, especially this requires leaving opinions behind–it is not worth delving into such things too deeply. So most people operate through two step process: does it fit the usual boxes of politics, and if it doesn’t, do I care, with the answer to the latter question usually being a big “no.”
The same is true with hitting a baseball, and presumably, with most other activities requiring a quick reaction: nobody who is any good is probably so simple minded to have just one box, so to speak. But most people will have just a few boxes, which, thankfully for them, would account for most of the universe. (The same applies to sabermetrics: most of these usual boxes will yield predictable results–i.e. high frequency of fly balls probably means the pitcher is not as good as his ERA indicates, for example–the idea behind FIPS) But if the expectations can somehow be subverted, you can fool the hitters. While a strange politicians who is not exactly liberal or conservative nor a Democrat or a Republican will confuse the voters and lose elections–becaused confused voters don’t vote–getting batters confused is a useful skill, if you are a pitcher, and all the better if you can confuse the sabermetricians along the way, because, that way, your methods might be so complex that the batters won’t be able to adjust to you easily either.