I wasn't necessarily basing his lack of ability to play CF on the arm, but it's a concern. More concerning is what multiple scouts say about his defense. He gets late breaks, is slow to react, and has exceptionally poor feel for reading balls off the bat. One scout on BP said Tapia had the worst baserunning instincts he had ever encountered. That obviously translates to the field.
Maybe that's overly harsh, it probably is, but if he could play CF then he would still be on the Rockies. The stats, the eye test, and the scouting reports say that he isn't playable in CF. I think that's a big problem for us. Grichuk was perfectly adequate for us in that regard. All of the routine plays were made. On the hitting side of things I don't think we lose a lot, but we'll see.