So you are saying that you would be asking the home plate umpire for help on whether or not a slapper is out of the batters box when making contact with the ball?
If that is what you are saying, don't sweat the boxes, because no way is the HP umpire going to grant you your request, and no way can the field umpire see that anyway.
If a batters box is your biggest concern... life is good. I am very critical of umpires in general, but that is a call that is rarely made, with or without boxes and is pretty damn difficult for them to see IMO anyways... well, unless the HP blue is not trying to focus on balls and strikes. Even coaches looking from the side view are only guessing. You think she is out of box, but I bet if you slowed things down and watched in slow motion youd be wrong more times than right.