Firm pitch counts are necessary becuase managers are dumb and too interested in the short term. You create a hard cap for them, and it's easy enough for them to follow. You tell them that it's a case by case basis based on whether his mechanics are falling down, whether he's visually laboring, what kind of distribution of pitches he's had, and you'll get buffoons like Dusty that tell you the pitcher looked good out there, or he told me he could go one more. None of this is to say there aren't severe flaws with giving the same idiots a # to work with.