A few months ago, I had a pinch puncture and a very rapid front tyre deflation descending White Horse Hill. This is very steep, very lumpy, and has a dead stop at the bottom for a crossroads. This has been a recurring nightmare ever since the Swindon RC club secretary told me of a horrible crash he once had when his front tyre blew on a descent.
Anyway, I hung my arse off the back of the saddle and braked as hard as I dared at the rear. I didn't touch the front brake because I could have pulled the tyre off the rim. With much fuckshitfuckshitfuckshit type of language, I rumbled to a halt with about five yards to spare.
I tend to let rip on descents and have had a couple of downhill incidents where I have locked up both wheels. Once was at university, when I was on the way down Dogpoo Lane in Birmingham, grabbed far too much brake and slid about 50 yards, stopping about a foot from the rear of the last car in the queue. The other time was going down a hill on Dartmoor, where I locked up both wheels of my Cannondale MTB on dry tarmac because I'd anticipated a left hand bend instead of a right-hand bend (tip, kids: use your eyes and don't assume you can remember every detail of a road). Apparently I negotiated the corner in truly spectacular fashion. The guy following me was a 3rd-in-the-UK BMX champion and said it was the best piece of bike handling he'd ever seen. He thought it was intentional
There was also a sky-ground-sky-ground moment when MTBing, where my mate was convinced I was dead. I didn't have a scratch but I couldn't get up at first because I ended up lying on a steep bank with my head a lot lower than my feet.
I'm not sure I'd do it if there was *no* risk...