We don't know the sale of the grades and we aren't even sure what they represent. It's certainly not just an estimate of a player's skill, relative to the rest of the league. The basic foundation must look something like this: Grade = Performance - Expectation GRADE: If a player matches his expectation (performance - expectation = 0), I'm not sure what grade that would result in, though. My gut says a C but that seems a bit harsh. Who knows? PERFORMANCE: How do they quantify performance? How a player impacted a game, in terms of runs and wins, is my guess, which is why RISP splits ARE relevant. I think something along the lines of WPA (win probability added) would be an excellent tool to use, to gauge offensive performance. It lacks some important information but it would be a good place to start. Anyway, here are the Brewer WPA's: http://www.fangraphs.com/winss.aspx?team=Brewers&pos=all&stats=bat&qual=0&type=3&season=2010&month=0 Offensively, Braun and Hart's offensive contributions impacted their respective games the most. If you want to adjust for opportunity (if a player gets to bat with the bases loaded and 2 out in the bottom of the 9th every game, his WPA will be higher), you use WPA/LI. That shows that while Fielder did not get as many opportunities to impact the game as hart did, he did more with them. For fielding, there's no WPA for fielding atm, so I would just use some mixture of UZR, general scouting and situational defensive performance. This is also where I would hope that a SS would get weighted more for his defensive contributions than a 1B. EXPECTATION: The expectation part of the equation is as important as anything else I've talked about so far. I would be fine with setting expectations proportional to the player's salary (feel free to make adjustment for pre-arby guys). I think that Tom and Witrado just make up expectations as they go, though. I doubt there is any real science to it. I mean, many questioned whether Hart should have even started and he ended up going to the All Star game. He still "only" got an A- though, so I have no idea what an A+ would look like. Of course, I don't know what a B, C, D and F look like, either.