As a caveat, the following is taken from BaseballSavant's raw MLBAM data spreadsheets of Miley's appearances (and for some reason one start is missing from the 2012 database), so it's not going to tie to the scrubbed Brooks data (There's also the very real possibility that I've made some busts myself).
I was looking at Miley's called strike numbers vs. pitches taken in the zone, and his ball numbers vs. pitches taken outside the zone (Brooks adjusts the strike zone for each hitter, which isn't done here- basically using MLBAM zones 1-9 as the strike zone).
I'm relatively new to the Savant datasets, but with every pitcher I've looked at, there is a greater number of strikes and fewer number of balls called than "should" be called (basically the called strike zone is larger than as defined by MLBAM), so the absolute relation between the columns in the graphs below isn't that meaningful. What jumped out at me was the change in 2014, where Miley appears to have benefitted from favorable calls at a much higher rate. Could be as simple as him working closer to the zone when he's outside of it and generating more borderline calls, or could play to the framing discussion. Or could just be bad data.
Also came across this article which I didn't see posted above discussing Montero/Miley success at pitch framings.
http://insidethezona.com/2014/09/montero-miley-match-pitch-framing-heaven/
First graphs shows % of pitches taken in the zone vs. % of pitches called for strikes
Second graphs shows % of pitches taken outside the zone vs. % of pitches called for balls.
Assuming the data is accurate, would seem that any improvement in Miley's performance due to framing is already baked in to his 2014 numbers. My concerns would be that despite the apparent rise in favorable calls, Miley still posted a career high walk rate, and also that the 2014 jump in K/9 may be more dependent on framing/umpiring effects than on any inherent improvement in Miley's offerings.
