the correct answer according to modern baseball - which is informed by sabremetrics, is to almost never issue an IBB. Here is a recent article on this question that was inspired by Tony LaRussa's bad decision to issue an IBB to a batter on a 1-2 count (after a wild pitch advanced the runner to 2nd):
https://www.espn.com/mlb/story/_/id/340 ... ry-rankingI play almost exclusively the Mystery set which is from the era of the IBB, so I guess it is reasonable to have IBBs programmed in since that is what teams did. Although, the article does mention that in 1974 Walter Alston's Dodgers only issued 9 IBB on the season (similar to present day baseball). Looking through my teams it looks like they tend to issue too many IBB for my taste (I'd prefer like 5 a year - tied or trailing late in games with one out and first open with runner on 2nd or 3rd and a weak on deck hitter). I almost always end every season set to extra conservative on IBB but I may not be paying close attention at the beginning and accumulate IBBs early on. I've never paid close attention to it, so I'm not sure if "extra conservative" is reliably effective in keeping IBBs in the single digits for a season.