Since Major League Baseball has implemented replay on home runs, has the batter's batting average increased due to the wait the pitcher has between pitches?
Probably no impact- The average wait time is probably around 2-3 minutes after replay. Pitchers wait a lot during baseball, and something as minor as 3 minutes probably has no effect- meetings on the mound, Manny Ramirez homeruns, and other minor events all make pitchers wait longer between pitches.
The only thing I could think of would be if ruling a HR a double and vice versa had an impact because of whether it made the pitcher pitch from the windup vs. the stretch. I always assumed that the windup was what most pitchers preferred (after all, they only do the stretch when necessary), but according to this article, there is no effect.