As of right now, there seems to be only a low appearance factor for hitters.

From the game manual:

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Low Plate Appearance Factor: If a player or pitcher has less than 10 plate appearances versus either left-handed or right-handed pitching, his actual performance will not be followed in the game. He will be assigned performance criteria which is below average major league offensive production for his position.
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This doesn't really mention low BF factor, it seems to only apply to hitters. My point is, there are several low usage pitchers that occasionally start a game.

Example:

SP Tanyon Sturtze

His LOPS is only .417 and his ROPS is a whopping 1.500

He faced only 2 RH, and 20 LH batters.

I went and looked at Tanyon Sturtze in several leagues and check his stats, specifically his splits.

In each of the ones I checked, he had a ROPS of over .900, while posting a LOPS around .400

Basically, it looks as if there is no "low BF factor" for pitchers since Sturtze got creamed by RH and got out LH with ease. I guess there's only a penalty for hitters. This might be an area to be fixed for a future version, so that some low usage LHP who faced only 1 RH batter and got him out, couldn't be used to shut down an entire RH lineup in 1 or 2 games.

Jon