The original post explores WPA. The thing about WPA is that it kind of breaks down as a useful stat in some cases. For example, a relief pitcher could throw 5 scoreless innings in a blowout, but if his team is 10 runs down in the 4th inning his WPA will be minuscule. Or, a reliever could get the last out in the top of the ninth of a tie game and if his team walks off in the bottom of the inning his WPA will be huge. I think there needs to be a stat which compares WPA in each situation to the best or worst possible WPA.