Buck Miller IV - Modern Draft League Manager

(1) Miller IV does NOT save a rotation; you MUST bench your starters to prevent their use in relief. Miller IV will use any pitcher that is not benched regardless of their grade, rating or stats (e.g., any relief appearances).
(2) Miller IV (like versions I, II and III) is NOT designed for historic or season replays. They are designed solely for draft league games. Use of the Miller managers in a historic season will lead to odd results or stats.
Buck Miller IV is designed to handle modern draft league only replays. He is not designed to manage season replays of any type. Although created to guide modern seasons, he may be adequate in handling pre-modern (e.g, 1990) replays depending on your team's roster.

Several important points to make:

1) Miller IV, as noted above, does NOT set aside a starting rotation. He will and does use any pitcher not specifically benched in League Manager or in your lineup/rotation setup. So, you MUST bench your rotation (or choose the "Bench Pitching Rotation" option in LM).

2) Miller IV selects closer by grade and not actual save totals. A reliever, for example, with zero saves but a high grade (e.g., 14 or higher) will be used over a reliever with high save totals but a lower grade. A "normal" closer will have an adjusted grade (grade plus control adjustments) of between 13 and 16. A "supercloser" will have an adjusted grade of 17 or higher. Miller IV will more aggressively use the superclosers than the "normal" closers. A good comparison would be the use of relievers in baseball with 12 saves versus a reliever with 30 saves. Obviously, managers used the latter reliever much more liberally in save situations than the former.

3) Generally, Miller IV follows the LaRussa one inning closer approach. That is, closers (both normal and super) will likely only pitch the ninth in save situations. Set up relievers will be heavily used before then. If a team has more than one closer, the lower grade closer will be used as a setup reliever for the superior closer. Miller IV will be, however, be willing to pull your top closer for a lower rated one if the top reliever is struggling and there is a grade advantage.

4) Miller IV (like I, II and III) hates to see relievers hit. You'll see a very aggressive use of double switches and "rearrangement" of the batting order to try and limit the times a reliever hits. Generally, unless the reliever is a "stud" pitcher or the game is lopsided or a team's bullpen is thin due to overwork, you'll likely never see a relief pitcher hit.

5) In addition to point (4) above, Miller IV (and the other manages) tends to "rotate" or use multiple relievers in games. Except very early in games (or where a team's bullpen is thin), you'll likely see Miller use 3-4 relievers over the course of a game - even in non-close games - where a reliever may pitch only one inning, two at most.

Note: One strong suggestion re this is to have, if possible, at least one long reliever on your roster. It's advisable to have one reliever who can pitch 2-4 innings in an emergency (e.g., starter gets hurt or ejected in the first or second inning). If you stock you team with quality relievers (relieving durability of 3) and no long reliever, you'll likely see Miller using one of the short role relievers for 3-4 innings.

6) Miller IV has a number of "bells and whistles" some of which may or may not be applicable to your team. For example, he has a couple of pinchrun to steal strategies (second or third) that may not apply to your team if you don't have a good base stealer on your bench (e.g., steal rating of 28 or higher). Additionally, Miller IV has a pinch hit to bunt strategy that requires a "good bunter" be available; a pinch hit for a hit and run situation (that also requires a bench hitter with a good H&R ability that includes a low SO/AB ratio) and a few other assortment yip-de-doos.