I wore one---sort of. The 125th Bull Run reenactment was held in a huge vacant field not far from the original battle field. The temperature was 100+, high humidity and scorching sun. There were thousands of reenactors, and the sutlers were doing a good business in havelocks. Sounded like a good idea to me since it was one of the few battles where they were actually worn. Unfortunately, as we were forming up, our "brigade" commander ordered all havelocks taken off, because his "research" showed that the brigade we portrayed were not wearing havelocks in the actual battle. We were in no position to ask for his footnotes, so I never got to wear it and it became a dishrag. I managed to avoid sunstroke, although I had to fall out with stomach cramps and had a sunburned neck as a reminder. I've never been at a reenactment with so many ambulances crossing the field during the action. Ah, memories...