In reply to Bertbee:
On really big roofs eg. the Grande Grotta on Kalymnos, you need to strip it in two goes - ie get the top half out by lowering off, and get the bottom half out on 2nd. Serious faff. If it is a popular route on a big roof, if you are lucky someone will have left an in situ krab, maillon, ring or similar, that you can clip your rope into as you lower down past it, which means you don't need to take such a massive swing on the subsequent clips.
clean nose quickdraws are a total godsend on these routes.