I'm not a sabermetrician. I wish I had the time and skill to be one but I don't. That said, I've never been on board with WAR. Fielding is the most difficult of the four aspects of baseball (the other three being pitching, batting, and base running) to measure. Did an outfielder miss catching a fly ball by one inch because he ran too slowly, because he reacted too slowly, because he misread the ball off the bat, because he took a bad route, because the sun (or artificial lights) affected his vision, because the coach positioned him improperly, because he positioned himself improperly, because his glove was too small, because the ball traveled more slowly due to cold weather, because the ball traveled more rapidly due to hot weather, because he was not 100% healthy, because another nearby fielder spooked him, or some combination of those and myriad other factors? Or was it a fly ball that was played as perfectly as humanly possible but simply wasn't going to be caught? I just think it's impossible to accurately and precisely quantify fielding. The lack of accuracy and lack of precision are compounded when trying to extrapolate fielding metrics into runs saved. And the lack of accuracy and lack of precision are compounded further when trying to extrapolate runs saved into wins and losses. The metrics attempting to quantify the other three aspects are also flawed, less so than fielding, although it depends on which metrics are used. However, there is still the same loss of accuracy and precision when trying to extrapolate those metrics into runs, and from there into wins and losses. So, WAR then. The way I understand it, there are several different formulas, none of which is totally objective, all of which use various imperfect metrics from the four aspects of the game (each of which is affected to some degree by the other three). And it's supposed to determine how many wins a player generates relative to some vague replacement player. While it's a noble goal, I think WAR as it is currently configured is too inaccurate and too imprecise to have much value.