Sabermetricians like to measure things. We enjoy looking at something a player has done, slapping a number on it, and taking pride in the fact that we're accurate. When we feel we may be inaccurate, we generally make sure to express that uncertainty. Sometimes, though, we get so caught up in our analysis that we disregard nuance; the result is often misleading, or even inaccurate, work.
Take, for example, catcher defense. Out of the area of baseball that infuriates sabermetricians more than any other, the indeterminate nature of backstops stands apart. Catcher defense has given us so many fits that it has its own section in FanGraphs' glossary. How much do they contribute or hurt their teams behind the plate? Does anyone know? Recent strides in pitch framing research (more on that in a second) notwithstanding, the field still doesn't have a whole ton of concrete evidence to support it.
Perhaps no one epitomizes the controversy over pitch framing better than Hank Conger. Drafted by the Angels in 2006, he showed up on numerous top prospect lists before debuting in 2010. This afternoon, Los Angeles dealt him to the Astros in exchange for a couple of minor leaguers. I don't really want to focus on the deal itself, on the merits of the pitchers Houston sacrificed, on its current position on the win curve, or anything like that. Instead, let's talk about Conger.
Scouts have never liked his defense. Kevin Goldstein's appraisals ranged from the ambiguous — in 2010, he called Conger "below average defensively" — to the (comparatively) concise — in 2011, he noted that Conger's "receiving skills still need work." With a .376 wOBA at AAA, he clearly had offensive prowess, but the glove would take some time to develop.
Then, Conger arrived at the show, and flipped the script. In his brief major-league career, he owns an 84 wRC+; even for a catcher, that doesn't impress. But against all odds, he has posted some formidable framing numbers: In 2013 and 2014, he ranked 6th and 3rd, respectively, in framing runs saved per 7000 pitches.
Thus, upon hearing of the aforementioned transaction, the media gushed over Conger's receiving. The Houston Chronicle said he has "strong framing skills", and MLB.com deemed him "one of the best pitch-framers in baseball". On Twitter, everyone from Mark Simon to Jeff Passan to Jim Bowden praised him.
So, is he really the god these pundits have made him out to be? Well, the numbers probably don't lie: The math behind them is freely available, and it seems to check out (although, as a non-genius, I can't really testify to the latter point). But there's another issue here: sample size. I'll again look to FanGraphs's glossary for clarity:
"...[W]ith any defensive statistic, you should always use three years of...data before trying to draw any conclusions on the true talent level of a fielder."
The moderately-misleading quote rings true, as does most everything on FanGraphs. So how does it apply to Conger? Well, in his two most recent seasons — the ones in which, you'll recall, he framed phenomenally — he racked up a combined...1172.1 innings. That's barely a full season's worth, and is far short of three. Prior to 2013, his framing was slightly below average, at -1.1 runs in 585.0 innings. Together with his weak status as a minor leaguer, this provides a convincing counterattack to the dominant narrative.
So what should we think about Conger? Maybe, as Jeff Sullivan wondered last year, he's actually improved his defense; rebuttals in the comment section of that post suggest otherwise. In my opinion, this smells of a fluke, or at the very least an unreliable sample. With the rush to scrutinize every little transaction of the offseason, my fellow sabermetricians shouldn't blow this out of proportion. We know better — or at least, we should.
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Ryan Romano is an editor for Beyond the Box Score. He also writes about the Orioles on Birds Watcher and on Camden Chat that one time. Follow him on Twitter at @triple_r_ if you enjoy angry tweets about Maryland sports.