If I had to describe Bruce Bochy's managing style in one word it would be "involved," and that's not just because "veteran fetish" is two words. Bochy has always been given a very slim margin of error where runs are concerned; such is the curse of managing for a low-scoring, pitching-first ballclub.
Squeezing runs out of the Giants roster hasn't been an easy task since the Bonds era, but Bochy has stuck with it, doing his best to make that "just enough" offense actually provide just enough runs to win.
One of his key strategies as Mr. Manager has always been working the lineup day in and day out to best optimize the starting nine against each specific pitcher, and while that sounds all fine and good, sometimes we need to ask ourselves if he's actually doing the right thing.
Right now, Bochy is currently using somewhat of a split lineup, as the lineup changes relatively drastically depending on the handedness of the opposing pitcher.
For example, in today's game against southpaw Clayton Richards, Bochy switched out Saturday's starters Brandon Belt, Emmanuel Burriss, Brandon Crawford and Nate Schierholtz for Hector Sanchez, Brett Pill, Ryan Theriot and Joaquin Arias.
The thought process makes sense: have an all-right-handed lineup against lefties and an all-left-handed lineup (except Posey) against righties. That seems logical, but handedness isn't always a surefire sign of a desired split.
Taking a look at the splits, we can see that, in the Giants' case, handedness actually doesn't mean much at all in determining which handed pitchers a player can handle best.
For example, Brett Pill, in his relatively short amount of playing time, has actually done much worse against left-handers than right-handers. His numbers against lefties are actually pretty terrible: .220/.289/.390 for an 89 wRC, compared with .387/.412/.710 and a wRC+ of 203 against righties. He also strikes out more than twice as much against lefties than righties and walks less against them.
Belt, on the other hand, has actually hit lefties much better than righties: .347/.418/.510 for a 164 wRC+ against lefties vs .201/.287/.379 for an 84 wRC+ against righties.
Hector Sanchez, one of the other platoon players, also features dramatic splits, but not in the direction Bochy apparently thinks: his numbers against lefties are .174/.208/.217 for a wRC+ of 15, while his numbers against right-handers are .350/.386/.450 for a wRC+ 134.
Schierholtz and Burriss also hit lefties better, despite the fact that they only really play against right-handers.
Now some of this data is based on relatively small sample sizes, namely for Pill, Belt and Sanchez, but when the numbers are so dramatically split, you can't help but notice and criticize. While handedness is a decent barometer for splits, Bochy should be doing more than just mindlessly plugging in hitters solely based on what side of the plate they bat from.