Fangraphs.com's Jeff Sullivan re-examines Ryan Doumit's career and his catching abilities. The results, like Mike Fast's framing study which started this line of thinking, are not good. Using CERA (minus the "earned" portion), Sullivan found that dating back to 2005 when Doumit was catching his team allowed 5.37 runs per game (CRA). When he wasn't catching, his team allowed 5.00 runs per game.
Here's Sullivan's analysis:
Thatís a straight-up, un-weighted average. On average, when Doumitís been behind the plate, his teamís allowed 5.37 runs per nine innings. On average, when Doumit hasnít been behind the plate, his teamís allowed 5.00 runs per nine innings. This does not adjust for playing time or for pitchers caught, so of course it isnít perfect. Thereís a lot of potential error in here. But this could also be capturing everything ó throwing arm, pitch-blocking, pitch-framing, game-calling. CRA is a hopelessly flawed statistic, but for whatever itís worth, it isnít kind to Ryan Doumit, which goes along with his defensive reputation.
Teams throw about 1,440 innings a season. Over 1,440 innings, a 0.37 RA difference is equal to about 59 runs. If weíre in any way capturing Ryan Doumitís true defense as a catcher, heís really not good at it, and his bat probably isnít good enough to make things much better.