I agree that its something that should be practiced. Teach your players to throw through the cut - off man. Teach your players to cut only if directed to do so. Teach your players to say nothing if they want it through and Cut-2, Cut-3, Cut-4 if they want it Cut. Redirecting Cut's and pre pitch cut calls should be practiced. Of course there is Baseball Feel that has to be brought into the equation. Throws that are dying, way off line, etc no one should have to say anything even though they should. The whole goal is to keep single's single's, double's double's, triples' triple's and not allowing runners to take bases behind lead runners they shouldn't be given.
We practice this everyday. It's part of taking infield each day. Add actual runners when you can and practice redirecting cut's based on how the play unfolds. You can also do this while taking BP. Have your defense practice cut's while your taking BP. This also is a good way to work on actual base running as well. Every time your working on the defensive side of a part of the game is an opportunity to work the offensive side as well.