If you look at last season's leaderboard for most appearances by a reliever, you will see four Braves in the top 10. It's the thing about Bobby that gets me the most -- his usage of the bullpen. He absolutely abuses his relievers while clinging to his righty-righty and lefty-lefty matchups. Peter Moylan, who was 11 months removed from Tommy John surgery, made 87 appearances, which was good for second in the majors behind Pedro Feliciano's 88 (At the beginning of last season, Cox talked endlessly about protecting Moylan, but instead, he gives him a career high in appearances. WTF?). Mike Gonzalez finished right behind him with 80. Eric O'Flaherty and Rafael Soriano finished off the top 10 with 78 and 77, respectively. Moylan, Gonzalez, and Soriano each pitched over 70 innings, but I'm more interested in O'Flaherty only pitching 56 innings.
Fifty-six innings! In 78 appearances! My mom complains about paying money to a guy who only gets one out a game, and while O'Flaherty really gets two people out a game, he still fits in that category. Honestly, I like O'Flaherty. He's effective, and because he's still making the league-minimum, I really don't mind having him as a lefty specialist (he actually did fairly well against righties with a .282/.375/.301 line, and his BABIP against them was .325 -- or their BABIP against him, whichever). I wonder, however, if he doesn't waste more energy in the bullpen than on the mound in the actual game.
And then I thought a little harder about the situation. Does the reliever expend more energy in the bullpen than in the game? Does he expend a similar amount? I imagine they throw something like 30-40 pitches in the bullpen before they're ready to come in, and when they come in, they usually last an inning (about 16 pitches on average) or less (fewer than 16 pitches, obviously). I guess they don't use as much energy to throw each pitch in the bullpen as they do in the game, but you can't exactly just soft-toss it in there.
When the reliever actually makes an "appearance" in a game, I don't really think it matters all that much. By the time you enter the game, your arm is pretty warm, and the extra pitches don't make a substantial difference unless you stink up the joint by allowing a few runs and throwing another 30 pitches (and then you kind of deserve the extra discomfort, right?). But what about when you don't make an "appearance" but still warm up? If the answer to one of those questions above was "yes" (and I think it is to at least the second question), then I think we might want to pay a bit more attention.
Again, the one thing I really can't stand about Bobby is the way in which he uses his bullpen, and his need for orthodoxy is only one part. I don't have the proof (though I hope this sparks some research for the proof), but I would put money down on Bobby being one of the worst transgressors in blue-balling relievers. Because of his need to stick to his R-R and L-L matchups, he has to get multiple pitchers up at once just in case, but the inning does not always require the extra reliever(s) to be used. Then when he gets to the eighth or ninth and could bring in Soriano and Gonzalez to finish off the game, the reliever(s) never made it into the game (It really bothers me when Bobby does this. When you get a reliever warm, you should try to use him, and a lot of times, he could have but decided to bring in someone else anyway. Kills me).
If it takes as much effort to warm up as it does to actually pitch, then a reliever who warms up but does not pitch still makes an appearance, at least in terms of effort. We measure appearances in order to measure how much a manager abuses a certain reliever (or in Bobby's, and Jerry Manuel's apparently as well, case, multiple relievers), but as I've mentioned, appearances don't measure all of the abuse (or use; "abuse" is maybe a bit harsh). Instead, I advocate that we also count times when the reliever warms up but does not get in the game. If they get in the game, then only count it as one appearance (not one for the warm-up and one for the actual appearance). So as soon as the pitcher gets up to warm up, mark it down as an appearance.
"Does this matter?" you ask. I'm not sure yet, but I also don't know the results of any research. Moylan made 87 appearances last season, but I'd be willing to venture that he made another 20 "appearances" or so, giving him 107 now for the season. I'd also argue that Bobby is worse about this than other managers. Let's use a hypothetical example (I don't know if Mike Scioscia is worse about this or not, but let's assume he is). Brian Fuentes made the most appearances by an Angel last season with 65. If we allow that Scioscia is better about getting warmed up relievers into the game, then we could say that Fuentes made an additional 10 "appearances". He now has 75 for the season. Instead of the initial 22 appearance difference between he and Moylan, it's was actually 32. Is that a significant enough difference? I'll let you decide.