Great anecdote, azcheesehead. It sounds like MLB could improve things by changing the umpire traveling schedule or giving them more off days. They are on the field for longer than anyone else. I'm somewhat surprised at the number of reviewable calls, but if it includes check swings, foul tips, etc. then it is definitely possible. The issue with a finite number of challenges is definitely there, but I think that it can be mitigated if the correct goal is in mind. For instance, the NFL's goal on reviewable plays is to get every single call correct. However, the NFL does not have any review for penalties and is still subject to games being decided by questionable pass interference calls or missed holding penalties. Scoring plays and turnovers are the most important to 1) the outcome of the game; and 2) the easiest to review, so they receive the most reviews. In MLB, the easiest play to review is balls and strikes because the computer already does it. However, balls and strike have a very low importance on the outcome of the game, except in certain high leverage situations. That's why I advocate for a fixed number of challenges for balls and strikes. If the manager uses them up on low leverage situations, that's his loss. The plays that are most important to the outcome of the game are home runs, fair/foul balls, and safe/out calls. However, we have seen that these calls have some potentially tricky situations such as where to place runners and how many challenges to allow. The umpires have a right to be concerned. But the most question is--are the potential issues/problems solvable? I think the answer is yes. I also strongly agree that a central review room is best.