I was reading the Help section in the Manager's Office - Player Settings - Edit Player Settings this morning. It has been a while since I have read that particular section and it reads quite a bit different now, mostly understandable even. I would advise everyone read that Help section over. The article I did on Spring Training still applies though. There are still some things they don't mention that can be worth knowing.
For one the hierarchy of pitcher selection of the bull pen is Long A/Long B, Setup A/Setup B then Closer A/Closer B. Which one the AI uses depends on the situation. For instance it wouldn't bring in a Long A in the 8th inning with a 100% Setup A/B available. I have seen it bring in a Setup A/B to finish an inning then pinch hit for him in the next inning or leave the Setup A in for the next inning if he can't be pinch hit for. Specialty pitchers rarely pitch also. It will bring in a Closer in the 8th inning if you don't have it set to 9th inning only. Every now and then the AI makes some rather strange calls in this area, nothing can be perfect I guess. One thing I have noticed is that it will try to hold onto a Long A/B pitcher forever in an extra inning game and may even bring in a starter before using him.
Pitcher Fatigue and recovery is tied to more than just durability and stamina as it alludes in the instructions. What it doesn't tell you about TPC and MPC may take a couple times through the rotation to actually understand and get set right. What you are trying to do is get those settings so the fatigue of a starting pitcher is recoverable one day before his next scheduled start so he can rest 1 day at 100%. That is how I try to do it anyway and not send his fatigue to a point where he becomes ineffective. Their answer is that a pitcher at 100% performs like any pitcher at 100%. Well I would say that is true, but is he really at 100%? That is the question they duck and cover on and never actually answer.
Bull Pen Pitchers can be a little more trickier in this regard. You don't want your Bull Pen to be pitching fatigued either. That is why I recommend setting the TPC and MPC so low. Besides, for the most part they only need to get through one inning+ most of the time unless something unfortunate happens to a starter.
Call Bull Pen setting is also very important. Most pitchers you don't want a setting of 1 and should only be used for the "Elite Starters" and Closers if at all. I normally use 3 for almost everybody at the ML level, minors is a different story. It is strong enough that the AI will not pull a pitcher at the first sign of trouble but will if it continues. I use 4 and 5 rarely but will for pitchers I don't fully trust and definitely in playoff games where it is a must win situation.
My team is really bad when it comes to pitching and it is something I have to correct somehow in the off-season but will use them as some Examples:
Dicky Woo is not the greatest starting pitcher on two feet and might make a Long A on most teams. He does have a great Stamina and makeup, health is decent and patience is average. With his durability I can set his TPC equal to 90 and MPC to 105 easily enough and will recover 25 percentage points of fatigue per day after a start and should be rested enough for his next start also. I would set his Call to 3 also. The drawback is that he might need all 90 pitches to get to the 5th inning...yikes...lol
Blade Thompson is a pen pitcher of dubious quality and I use him as a Setup B. If it wasn't for his control and pitches I would relegate him to AA or AAA. His Durability and Stamina limits him to a TPC and MPC of 15. With his low makeup he will fatigue more quickly and recovery could be slowed also. Even at 15 pitches he may be only able to pitch every other day and that might be a big maybe.
I have never noticed, but I wonder if makeup of position players plays a more important role in on field performance than we are led to believe after reading this.