As a coach you should be happy when an umpire gives that kind of direction to your team. Would you prefer he calls the girl out for running outside the lane, or out for not having her foot in the box, or award the other team a base because your catcher is a little to close.
The potential downside here...What if the umpire is giving your players BAD advice?
There's no rule that says a batter-runner MUST run inside the three-foot running lane. So I hope that no umpire would ever tell a player that.
There are rules that say the batter must be positioned within the batter's box BEFORE a pitch can be thrown. I certainly hope that an umpire would never call a batter out for being out of the box BEFORE the pitch is thrown.
A catcher being too close is both a safety and a rule issue that we are specifically to address. But no umpire should ever award a base just because a catcher is "too close".
And what if...A coach takes exception to the advice you're giving or even the fact that you're speaking to one of his players? Now you have a bigger problem on your hands- a ticked off coach. I've seen it happen before.
What if you give your "friendly advice" to a player on team "A", but fail to do the same for a player on team "B"...then the player on team "B" subsequently commits a rule violation that you averted the other player from making with your advice? You have- whether intended or not- given one team an advantage that the other team was not offered. Somebody might not be too happy about that!
Of course, no umpire should ever be telling a player how to hold a bat, bunt the ball or deliver a pitch. But if you think "some" coaching advice from the umpire is okay, how much is too much? There aren't any guidelines to tell us some things are okay to tell players, while other things are not. Where do you draw the line?
Our training draws a pretty clear line for us: Don't coach the players!