I had that except for Washington OF vs. Boston, and lost like 10 WAR. That seems off. Harper, Turner, and Werth vs Betts, Bradley, and Benintendi? That doesn't seem all that off. By fWAR it's like a 7 win difference, but that's partly because Benintendi only has 34 games. Not sure how exactly they figure it, but my point is the Red Sox OF is much better.