Many in the media denounced the trade as counter to the Sox' sabermetric philosophies - Pena's a swing-and-miss type of guy, with a low batting average and OBP, who is capable of hitting the ball a country mile when he connects. A latter-day Pedro Cerrano, if you will, except that he's only 24 years old. Erstwhile Mets GM Steve Phillips (and I like Steve Phillips, for what it's worth, but I didn't have to live through his acquisition of Mo Vaughn, either) was perplexed by the anti-Moneyball nature of the move.
As usual, the mass media is missing the point. The Moneyball philosophy seeks to exploit market inefficiencies - and those inefficiencies change over time. In the Arroyo/Pena example, the Sox traded a player with an average skillset (regardless of whether I like Arroyo personally, and I do, he's the definition of average) at a position where they had a substantial surplus for a young guy with elite power skills and unpolished on-base skills. Pena's high K rates and low average combine to create a market perception of his value that is below the Sox' opinion of his actual value. SoSH member Carroll Hardy puts it much better than I do:
Add to that the fact that Pena's under contract until 2008 at low cost, that he's a right-handed hitting right-fielder who can platoon with Trot Nixon, that he's a Dominican who reportedly bonded with David Ortiz during the World Baseball Classic, and that he's another silly-named outfielder, and this trade's a big win for the Sox.
1. He has certain specific, elite skills that are both demonstrable (scouting)
and measurable/repeatable (sabremetric). Just because they happen to be ISO (MLC Ed Note: statgeekage alert - ISO is isolated slugging) instead of OBP is immaterial. He has elite skills.
2. He has also demonstrated that there are other skills/traits that he does not currently possess, and may never (MLC Ed Note: OBP and average). It is the combination of those two statements that make him valuable. Merely possessing elite skills does not make him valuable (as opposed to expensive). What makes him valuable is that those elite skills are discounted precisely because of his shortcomings (perceived or otherwise).
I'm bummed to see Arroyo gone, especially in the wake of his really stand-up comments after the trade (note to Johnny Damon - that's how a professional conducts himself after a business transaction that doesn't go exactly how he planned). Another of the 25 cast to the winds, but in a manner that makes the 2006-08 Red Sox better. It seems every day I'm reminded of the fact that this Sox ownership/management group is the best in my lifetime, and probably the best in the club's history.