How far under are we talking about? He's at .340 after last night and we're just about at the half way point.
I suppose it's possible that he could hit .260 the rest of the year, especially if he gets injured. But barring that, I think it's unlikely because there are concrete reasons for his improvement and it doesn't seem to be luck. Plus, he's had some swoons in production earlier in season, everyone in here says he's coming back to earth and then he picks it up again.