Span's OPS dropped from his rookie season before he had any concussions... But regardless, to me, Revere's problem isn't pitch selection, which is why I don't see much improvement in OBP/OPS (will always be driven by his average). My reasoning: He's actually pretty good at taking pitches I think, but he's also much better than most at making contact with the ball when he swings. Mauer is a great "hitter", right? Well, Mauer has K'd in 13.4% of his Plate Appearances this year. Revere? 8.0%. When he swings, he puts the ball in play. I am convinced if you looked it up (perhaps someone here knows how), Revere would have a very far below the league average swing-and-miss percentage. He doesn't foul that many balls off either. What I'm getting at, is if he swings, he is almost assuredly putting the ball out there for someone to have to field. If he wants to improve his OBP by drawing walks, he's going to have to leave that bat on his shoulder far more often than he is capable of, I think, because of this. He's a great "contact hitter", which in his case, is a detriment to the On-base skills you're hoping he can develop.