This past off-season, catcher Mike Matheny signed a 3-year,$10.5 million deal with the San Francisco Giants. Matheny is a three-time Gold Glove award winner who caught for the St. Louis Cardinals from 2000-04, during which time the Redbirds won four division titles and a pennant while averaging 95 wins a year.

Baseball observers might not spontaneously burst into flames in their excitement over the signing of a career .239 hitter, but one would think they would acknowledge that, at the very least, Matheny has not impeded his teams’ success. In fact, he must be doing something right – despite his worthless bat, he has contributed to consistently excellent teams.

Matheny has a great reputation as a defender, from blocking pitches in the dirt to handling pitchers, and his reputation is lent weight by the consistently surprising success of the pitchers he catches. Statistically, it’s not hard to see how that value could make up for the two wins his bat costs. Unfortunately, Matheny’s real value is at this point almost impossible to quantify, and that sometimes leads to people pretending it doesn’t exist.

The reaction from analytically-inclined writers and fans was typified pretty well by Tom Gorman, who runs the fine www.Fogball.com site, which is dedicated to the Giants. The crux of Gorman’s argument was that the Giants already had a fine young catcher, Yorvit Torrealba, who is a superior hitter and whose defense compares favorably, on paper at least, to Matheny’s.

“I want to stab myself in the eyeball,” Gorman wrote. “Sheer lunacy…. Easily the worst deal for any team this off-season.”

Some were harsher – one Giants fan, writing on his blog, compared the signing to “drinking rubbing alcohol and hitting on my brother’s wife.” Others were more moderate – this year’s Baseball Prospectus annual said that Matheny “didn’t warrant” the deal. Either way, there was a strong consensus among statheads that this was an obviously terrible move.

This is an area in which there’s some serious disconnect between devotees of objective analysis and observable reality. It’s pretty common to hear light-hitting backstops like Matheny discussed as if they didn’t belong in the major leagues – just as it’s pretty common to see them written up by self-styled traditionalists as if they were among the best players in the game.

While the statistically-based lens is often a good one through which to view the game, I think catching is probably an area in which it is not. We shouldn’t ignore the insistence of players and managers that traits like pitch framing and plate blocking – which we can observe but not measure – are of tremendous value to a team. The same goes for the stress that good teams have always put on a catcher’s ability to handle a staff and call a game. Statistics can’t capture that, which is why teams rely on observation and reputation to assess its value.

Part of the reason teams like the Giants consistently win when they “shouldn’t” on paper is that they’re simply better at observing and judging when the reputation of a player like Matheny is justified and when it isn’t.

It isn’t necessarily a bad thing that objective analysis can’t capture the true value of a player like Matheny; every way of looking at the world leads to certain blind spots. But as more fans, writers, and teams come to view the game through sabermetric lenses, we’re seeing new blind spots developing, ones just as large as the old canards about how some players have mystical abilities to drive in runs. Comparing the signing of a Gold Glove catcher to drinking rubbing alcohol is a prime example.

Mike Matheny is a good ballplayer, and I say this with great confidence. What evidence do I have? Statistically, not much. He’s among the game’s worst hitters, and catcher defense is almost impossible to quantify. The real effect of catchers on ERAs, for instance, is elusive because of the sample-size issues inherent in measuring how pitchers perform with backups who play 30 games against starters who play 130. Advanced defensive statistics for catchers mainly measure range and effectiveness against the running game – not the most important parts of defense behind the dish.

Without statistics, though, I can point to the fact that Matheny’s teams won four division titles in five years – teams don’t win 95 games every year without contributions from all their starters. I can also point to the fact that a well-run team, the Giants, thought he was worth a three-year-deal.

Interestingly, Matheny is far from the only no-hit catcher whose teams have been ending up in the playoffs. I checked the statistics for every playoff team over the last five years and broke their catchers down into three categories using OPS+, which measures a player’s park- and league-adjusted OPS on a scale where 100 is average. The first category was for the bad hitters, whose OPS+ was 90 or below; the second was for average hitters, whose OPS+ was 91-110; and the third was for good hitters, at 111 and above.

Of the 40 catcher seasons I looked at, 16 were from bad hitters, 10 from average ones (most closer of them to a 90 OPS+ than a 110), and 14 from good hitters. Jorge Posada accounted for more than a third of the final category.

Of the bad hitters, many were spectacularly awful. Matheny, Ausmus, Dan Wilson, Henry Blanco – these players swing some of the worst bats in baseball. And yet they are regarded as valuable, and their teams tend to win. It is possible that their teams are winning in spite of them, and that their defensive reputations are inflated in inverse proportion to the impotence of their bats. I think it more likely that their gloves are more than making up for their bats, and that we just don’t have a way to measure that yet.

To put it another way, of those 40 catcher seasons, I identified four – one from Mike Piazza, two from A.J. Pierzynski, and one from Bobby Estalella – from good-hitting catchers who don’t have good defensive reputations. There were 19 from no-hit catchers with reputations as good glove men.

There is a long way to go in appraising what goes on behind the plate. But in absence of convincing proof that players like Matheny stink, it’s probably best to assume they don’t. There are a lot of reasons the Giants might not make the playoffs this year; their Gold Glove catcher isn’t among them.