Aquaintances of mine were in Kalymnos a couple of weeks ago and one team apparently managed to get their 80m rope stuck after abbing off the top pitch of 'Massalia' 6b at the Grande Gotta. They were too tired to prussik up and free it, so cut both ends off, tied them together and managed to get down. I can't fathom out how a rope simply threaded through two bolts can get jammed so badly that it couldn't be pulled in either direction, so would welcome any knowledge from people there.....