I can testify that, within a saber-oriented F.O., a great deal of thought goes into trying to figure out who is undervalued by all but the smartest analysis. If all GMs were doing that, it would be pointless, and there would be no economic reason to hire sabermetricians.

If he tells me something, I assume the exact opposite is true.

What message board posters are usually arguing, as in the Johnson/Prado example you cite, is that a GM is foolish to deal someone (Johnson) because his leverage is reduced, and he has a weaker hand. Wren knows Johnson’s value, and an opposing GM may value Johnson exactly the same, but Wren is still at a disadvantage because the opposing GM can make a convincing argument that Johnson is actually worse than both GMs really think he is, and there are plenty of non-talent arguments, too (i.e. “Our fans won’t accept a deal like that;” “The media would eat me alive, and you know it,” etc.)

While not an insider myself, I imagine there are lots of other factors involved in why trades do and do not happen other than player evaluation. For example, why has Brian Roberts not been traded the past couple off-seasons? It’s very likely (almost certain) that the Orioles could have made a trade that benefited them, but they didn’t because Roberts is the “face” of that franchise, and Angelos didn’t want to further alienate the fanbase.

So while I agree with the point of your article, I think you’re ignoring a big part of the dynamics of negotiations.

I don’t know much about game theory, but I imagine it is relevant here, too.

http://www.weei.com/sports/boston/red-sox/alex-speier/2009/11/08/why-adrian-gonzalez-may-remain-limits-sox?page=full

And partial quote:

“When you value players the same way, sometimes it’s hard to make a deal than with an organization that emphasizes different attributes of players. If you have different evaluations, you can get a deal done quicker.”

I had not read that opinion, and I think it’s interesting to get his take. But, I’m not so sure he’ll be dealing less with Hoyer. Billy Beane has made many deals with his former associates and saber-minded GMs to the point where it almost seems that he prefers dealing with them. Five years ago, I wrote up a post explaining why the saber-GMs were trading so much with each other. Here’s what Beane had to say.

“We have similar beliefs and knowing each other allows us to make deals [quickly]. With J.P. and Theo, I can get a deal done in five minutes.”

It stands to reason that if different styles exist among GMs, then one style must be more accurate than another.

One might make the argument that different styles are dictated by different conditions.The most important difference being market size, which might explain differences in style more accurately than classifying them “right and wrong”.

However, going back to Epstein’s comments, he was referring to Boston and San Diego, two very different markets. Yet according to him, each leader still preferred similar evaluation methods.

While the different methods among GMs may all be more accurate than some fans believe, I think there is still enough of a difference to classify one as more accurate than another.

but it still doesn’t explain how players like Adrian Beltre and Gary Matthews can get monster contracts when they’ve done so little to earn them. Also, this may be deviating from the path here, but how come GM’s routinely sign pitchers such as Carlos Silva to contracts that all fans can see are not worth it? They could get similar performance from career spot-starters or long relievers for pennies on the dollar.

But often a particular FA is worth more to some teams than others. How much would Sabathia have been worth to Kansas City? That doesn’t mean the GM can’t overpay, but I’m not sure they consistently overpay ex ante.

In fact, my own unsubstantiated theory is that mid-range FA’s, who will often be commodity types, are the most likely to be overpaid, and that the ones at the low and high ends are paid more accurately.

Under that condition, there would be no GMs with good reputations (Brian Cashman, Theo Epstein, Pat Gillick) or bad ones (Moore, Minaya, Bowden).

It may well be true that Warren Buffett’s old doctrine about “good” managers and “bad” companies applies here as well, but the evidence of trend-following noted above makes it clear that the market can be arbed. (Whether it is worth the trouble to do so is a separate, interesting question.)