"Called Strikes Above Average" (CSAA for short) is Baseball Prospectus' newest attempt to quantify catcher pitch-framing, and it has some interesting things to say about all three Red Sox catchers of note: Blake Swihart, Christian Vazquez, and Ryan Hanigan.
The introduction to CSAA is as long and complicated as you might expect given the murky nature of pitch-framing. If you're interested in the gory details and what's changed since their last attempt, you can check it out tables, charts, and all here.
For those just looking for the Red Sox related bullet points, the news is good. Included with the report are some of the top performers in CSAA both current and past in the majors and minors. Let's start with the latter, where Blake Swihart makes his appearance on the Double-A list coming in at third with an estimated 20 runs saved by CSAA. While that puts him a long ways from the otherworldly Austin Hedges (37 runs, believe it or not), put in context that figure is quite strong, coming in a good four runs above the best Triple-A had to offer.
Historically, Swihart's season looks deceptively good. For instance, it would come in just outside the top-20 seasons from 1988 to 2008. It's a trend that the folks at Prospectus explain is likely a result of changes in umpiring:
You will notice that all of these top seasonal values arise from 2001-onward. We think there is a good reason for that. Before 2000, the umpires used to work exclusively in one league or the other, reporting to the respective league - not MLB - office. In 2000 the umpires were consolidated into one universal staff. In 2001 we may have seen the first real impact of that change: more called strikes.
The second big jump on that chart began in 2009, and coincides with the adoption of PITCHf/x. This also does not seem like a coincidence, as MLB umpires switched from Questec to PITCHf/x for evaluation that same year. PITCHf/x also informed us a great deal on the value of framing, and here we are with framing all the rage.
This spike has helped Ryan Hanigan jump into the upper echelon of catchers since 1988, coming in 20th with 69 runs saved. The rest of that list is a who's who of some of the game's best defensive catchers throughout the years, including former Red Sox Jason Varitek and David Ross.
It's the man Hanigan will be sharing duties with, however, who could blow right past him in a hurry. While Christian Vazquez didn't get a full season's sample size behind the plate last year, over the course of a full season CSAA predicts he would have saved the Red Sox an impressive 31 runs. That's actually a little less than the old system had him pegged at, but still good for third place in the majors.
Take this all with as many grains of salt as you feel necessary. The study of pitch framing is still relatively new and uncertain compared to other areas of study in baseball, and taking these numbers to show that, say, the difference between Christian Vazquez and Jarrod Saltalamacchia framing pitches is fifty runs. Still, if the Red Sox rotation goes above and beyond all expectations next year, there's a pretty good chance the guys catching them had a lot to do with it.