I've got one.....
....made of kevlar and we've been flaking it on the boom all its life (3 years). Believe me when I tell you that flaking the sail on the boom is not going to shorten the sails life. Abusing it while sailing will. Leech flutter is a major cause of fabric breakdown. I see boats under way ALL the time with their leeches fluttering and the skipper is clueless to the damage he's doing.