Just to let everyone know that I did get rescued this morning from the bottom of Ide Hill. Having the rear hanger snap off, and the mech wrap around the back wheel was not ideal, but at least it happened at relativly slow speed. The back wheel just locked up. I hate to think what would have happened if it been at high speed !. General comments of "the things people do to get out of riding up Ide Hill" were not that helpful ! Thanks guys.