I nearly had an incident on a hill that unexpectedly steepened when I had run out of gears and I realised that I was going so slowly that the mere action of unclipping would cause a complete loss of motion and the vertically of the bike; it encouraged me to make it to the topI didn't discover that until I came to a stupidly steep hill, decided to walk up it, but then discovered that I couldn't unclip the foot on that side. Fortunately, I started falling the other way and was able to get that foot unclipped in time!
