Again with the OPA!
Pizza Cutter asks (and answers) how reliable some aspects of fielding are from year to year. There are some interesting results here, including this one: …most measurements in the OPA! system begin to become less consistent year-to-year as you move from left to right in the outfield. Weird.
Very weird, but not inconsistent with other fielding systems. Why is this?
Dave Studeman was called a "national treasure" by Rob Neyer. Seriously. Follow his sporadic tweets @dastudes.