Add new comment

...is that in terms of plays on the field - discrete events over which it can be clearly established that catchers played a role, the catcher is nearly worthless defensively. And that is all SABR can see. The things that it can count. But sabermetricians all agree that this isn't fair. So they invent ad hoc methods of fairly evaluating catching skill...position adjustments and the like all came from that.
I am even guilty of this, though at least I'm honest about the source of my assumption. When I look at HOF and all time player rankings, I give catchers a 40% bonus because the top catchers are that much less valuable than the top players at other positions with the explicit assumption that catchers fail to capture normal value due to the physical demands of the position. That's...cheap. But there you go.
I think we need to find a way to rate the impact of catchers on pitching staffs...and no, I don't think that's an impossible task. But that is where the true value of catching is hiding (along with the position scarcity, which can be measured by looking at the full distribution of player performacne position by position and curve-fitting to account for positional differences, rather than making a linear addition that is bound to overrate and underrate certain groups of players.