Wed Sep 30, 2015 1:52 pm
In my understanding, playing "infield in" impacts only when the opposing team has a runner on third. In case of possible bunts, I believe that Hal decides on its own to bring the corners in independently of what your settings are.
So assuming that I am right on what I just wrote, here's the difference between playing "infield in" or not.
If the infield is in,
BAD: all "#" symbols on the Super-Advanced Fielding Chart turn from outs into SINGLE, AND all card readings with a "+" next to them (e.g. gb(ss)A+) turn into SINGLE. Overall, you give up almost 10 more chances of singles to your opponent---a .250 hitter becomes roughly a .300 hitter. Also, you lose all double-play chances EXCEPT on a gbA with bases loaded.
GOOD: the runner on third doesn't score UNLESS on a gb(B) if HAL decides to send the runner and the runner beats the throw.
So conversely, if you play back
BAD: the runner on 3rd always score on a ground ball (unless you turn a double-play with runners on first and third and one out)
GOOD: you turn the double-play if there are runners on first and third; you reduce the onbase by roughly 5% ---so taking together, you reduce the probability of allowing a big inning and losing your starting pitcher (5 runs in one inning) by some percentage (say 1%-2% maybe).
I guess there would be a way to compute all probabilities and figure out which option allows the least expected runs, but the overall logic is that, by playing in, you play a "double-or-quits" game. The decision really depends on your tolerability of taking a risk.
Traditionally, teams built on the small ball strategy tend to play "in" more often and teams built for Coors stadiums tend to play back and limit the big inning---especially if your bullpen is weaker and your starters are your best pitchers.
I would also guess that the best option, to some extend, depends on the availability of ground balls on your pitcher's card and on your opponents offensive cards, and the proportion of gb(A) vs gb(B) and (C). If there are very few gbB and gbC on your pitchers' cards and opponents hitters, you might want to play back as much as you can, since the benefits of playing in will be highly reduced.
On that note, you might think that the GB and FB that you find on the misc page of your roster might inform you on this topic, but really it doesn't. GB doesn't reflect ground balls---it rather reflects how many rolls have been targeted to infielders (GB) as opposed to outfielders (FB). So a single (LF) will count in the FB column, and a lineout (1B) will count in the GB column.
Hope it helps!!
