Year after year, Leon does better with more pitchers than Vaz or Swihart. I guess you want to chalk it up as luck.
Yes, pitchers have up and down years. Yes, it's not always the catcher's fault, if they do badly. Yes, luck and timing plays a role.
3 years of similar outcomes are not something to just ignore.
I provided the data for 3 years. Call it noise, if you want, but when the seven returning pitchers who had 60+ PAs with both Leon and Vaz all did better with Leon, and 5 or 6 did way better, I'm not DFA'ing Leon, until I see Vaz has improved in this area.
Swihart has a long way to go to get even with Vaz, let alone Leon in this area.