I was listening to 670 THE SCORE earlier today, and heard a strange comment by Mully and Hanley. Mully and Hanley tried to say "hey look, we love Jim Thome and appreciate all that he's done for Chicago, but he was only a 1 WAR player last season" (in actuality, Thome was a +1.5 WAR player in 3-4 months (he did not play in NL-interleague games) of ABs for the White Sox as a DH, and a -0.2 WAR player off the bench for the Dodgers in extremely limited ABs). Bless their hearts for trying to use Fangraphs and sabermetrics to support their arguments, but it's important to use the statistics right for them to be valuable and effective.
True, Thome is aging, worth "only" about +2 WAR pr 600 PAs and is also limited by both age and health to a DH-only role. +2 WAR is still valuable, but let's just say it's not enough for the Sox. What Mully and Hanley didn't account for, however, is that DH's generally have limited value in general because they provide one-side of the game contribution and get a -17.5 run reduction (-1.7 WAR) from their batting line. In other words, any DH is inherently less valuable and going to have limited value in comparison to "other baseball players" who play the field.
If you are signing a player in general who will play the field, you want a guy who will maximize his total contribution. In the average player, this contribution is a combination of position, offense and defense. Because there are more inputs for the non-DH, a non-DH who does not have Adam Dunn-like fielding abilities will inherently have a higher WAR; especially if they play a premium position like SS. The higher the WAR, the better the player. Teams want +5 WAR guys over the +3 WAR guys and the +2 WAR guys over the +1 WAR guys.
However, the perspective of evaluation must change slightly when you look to sign a DH-only player. A DH-only player only contributes offense. His WAR will be negatively impacted by the fact that he is a DH, no matter how good his bat is. If player A and player B are both equally good at offense, but player A is an average defensive LF (-7.5 run adjustment, +0 fielding runs) and player B is a DH (-17.5 run adjustment), WAR would not be the best method to evaluate which player to sign if you are looking to sign either A or B to a DH-only role. Player A looks better because his WAR is likely to be a full integer higher than B, but that does not mean A will be more valuable than B in the DH-only role. What teams should be looking at when evaluating prospective DH-only role players is not "who had the better WAR," but who had the better Batting Runs Above Replacement (BRAR) line.
Quick tangent, on that note: Rotating mediocre offensive players, whose total value comes from all-around play, through the DH role is a terrible idea. The DH exists to maximize offense. Omar Visquel, who posted +1.3 WAR in limited action (62 games) last season, will not translate into winning additional games if you play him at DH.
You want a guy like Thome because all he can give you is batting and he does it quite well. As I mentioned before, it is one thing if you are someone who can play OF or 1B or whatever. If this be the case, then by all means, please use WAR to compare and contrast players. Here, you want the healthiest, most all-around contributing player. However, this is a DH-only situation for Jim Thome and any team looking to sign him is looking for a DH-only player to play only DH. In this situation, you need to look not at WAR, but BRAR, and note that a DH-only player is bound to have a more limited WAR than comparably good hitting non-DH-only players.
Of all DH's who received 250+ PA's last year, only three (Adam Lind, Jason Kubel and Hideki Matsui) had WARs higher than Thome (who posted a +1.5 WAR mark as a DH for the Sox). Of those three, only Lind was worth +3 or more WAR (+3.7, to be exact). Additionally, all three of Lind, Kubel and Matsui received somewhere between 100 and 200 more PA's than Thome did in 2009.
Thus, we cannot evaluate a DH from last season, who we are prospectively signing as DH for this season, and say "oh he's only an X WAR guy." Obviously the guy whose slightly good at defense and offense combined and plays a valuable position will be worth more in the field, but as a DH, it's about one thing and one thing only. What's your batting line? And Thome's is still good.
ADDENDUM: I would also here like to here quote an earlier post, as I feel this comment is quite relevant to this overall argument:
"As a RF, Dunn's cumulative batting and fielding production gets a -7.5 positional adjustment (UZR measures all defense equally; Fangraphs accounts for differences in fielding difficulty between positions in WAR calculations thru positional adjustments). As a DH, Dunn would get a flat -17.5 positional adjustment and a zero fielding rating. In other words, as a DH, Dunn just get -17.5 runs subtracted from his batting line. As a RF (or LF, for that matter), Dunn gets -7.5 subtracted from his batting line in addition to his lackluster fielding. Thus Dunn, like anyone with a consistent -10 or worse fielding glove at RF/LF, belongs in a DH role."The same holds true for any 1B who plays with a -12.5 FRAR (Fielding Runs Above Replacement) or worse glove. They too, like the poor outfielder and frequently unhealthy slugger, belong in a DH-only role. The thing is, it's very hard to be that bad at first base...only Adam Dunn was at least that bad last season...