I don't think so, unless you are a fantasy owner. Aside from one season, he never stole bases with great efficiency, and his OBP isn't really high enough to make it an issue anyway. He is still fast enough to leg out a lot of doubles, and his XBH are his main asset. If his bat speed goes, that's an issue. I'm much more concerned with what it does to his defense. Great range in left was a major part of his value. It'd have to be a pretty significant loss of speed to drastically reduce his range out there. Plus you've got Pie out there often covering a lot of ground.