I really like what the Brewers have begun doing. They have 3 levels of pitch counts in the minors... pitches in an inning, pitches in a game, and pitches in a season (total IP pitched). At first glance pitches in a inning may season a bit weird, but if you think about it, is pitching 7 innings that each last 15 pitches more fatiguing, or pitching a single inning of 40 pitches? When a pitcher is only going 15 pitches at a time there are periods of rest and recovery, pitching 40 straight pitches is incredibly taxing on the body. Think of it in terms of weight lifting. You do it in sets with a short rest between because your muscles get tired. Tired muscles are more likely to get injured and are not as effective. If you do to much in the early sets you are not going to be able to do as much in the later sets.