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... presuming that there's any CERA-type influence that takes place in reality. (Which I DO presume.)
Pitch framing was recently "discovered" -- because they found a way to measure it -- and is now all the rage. That alone has a swing of +20 runs to -20 runs over the course of a season.
But five years ago, saberdudes would have scoffed just as much about Eric Wedge's beliefs on framing, as they scoff now about CERA.