Adding to some history here since Charlie hasn't been class measurer for a while. The class added carbon poles to be class legal when the rules were updated in 2005. The requirement for the bridle was removed then. There are no requirements in the class rules for a bridle on the spinnaker pole.
When I had a carbon pole on Rhapsody I did use a bridle as I thought it provided less stress on the pole rather than a ring in the middle. I had previously moved the twings so they attached to padeyes on the deck near the shrouds, thus removing the need for a pole downhaul and simplifying pole control.