The Rohloff requires a pretty wide chainline (54mm I think), so using the middle position and moving to the outside if you get a Rohloff makes sense. My Rohloff bike has a Sugino chainring guard and it is mounted on the outside of the crank spider along with the chainring.
Looks like this:
On my Bike Friday I'm using their stock chainring guard (they used to make them by cutting off teeth, now they seem to buy them ready made) also on the outside of the crank. I went with a very short BB in this bike to get lower Q-factor with the moderately wide Shimano 105 cranks. No photo of that setup, but it works well.
alex
