The box is only an issue if you let it become one.
Some coaches have no idea where they are at, and with them a quick, "Where are you at coach," on the way by usually snaps them back into awareness.
If it continues, it needs to become, "Coach I need you to stay in the coach's box," again in passing and without drawing a lot of attention to it.
Now the coach that is out of the box and not coaching, is another matter. If they are out and yelling, the coach's box is no longer an issue for that coach.
