Never do this. Anytime team-A is inside the 10, I and the box man repeat the yardline we are on to on another. It's no big deal to get back to that spot to within a couple inches.
I know this is a new mechanic in the NFHS manual for 2008, and I'm one to follow and preach following the manual, I just don't see the need, same as the clipping at the goal line mechanic.

Don't do this at the NCAA level either, but then the ball position is recorded on a chart kept by another "chain" crew member for every play of the game.
I can think of maybe one game or possibly two where the chart assisted in the placement of the box after having the box man to drop and run. Remember it takes a previous spot enforcement foul to occur at the time the box was pulled away from the sideline.

We discussed the golf tee in our area meeting last week. All the officials in our association agreed the golf tee is a liability that as an official we're not going to take. A player could easily dislodge a tee sliding out of bounds and then you've got a lawsuit. We don't like the beanbag, but agreed that at least for friday nights we'll give one to the box man.