I've ridden suicide hubs and not died. Always had a brake.
At first the cog was just tightened on with a BB lockring. I bought it used, and was a super-noob, so I didn't realize the danger. Anyway, I tried to skid for the first time down the hill to my work building. The cog broke loose, and I braked to a stop. I pedaled forward again once I was at the bottom, and rode home without incident, didn't try skidding again.
After that, I rotafixed the cog back on with some blue loctite and hammered on the BB lockring with loctite too. I learned to skid on it like that and rode it for a few months without incident (Except the QR breaking, but that's another story..)
Originally Posted by sivat
Should the cog come off entirely while skidding/backpedaling, it is possible for the chain and cog to catch against the dropout/chainstay and lock your back wheel. Probably, in the process, really screwing up your frame. I'm not saying this is likely, just throwing the possibility out there.
This is also possible with track wheel if you don't have enough chain tension and/or a bad chainline. I have dropped my chain plenty of times due to me being stupid, and often times the chain does get caught near the dropout. It just locked up the wheel and skidded me to a stop. That's it. I'd have no idea how you would twist up your frame from the wheel locking up, since that's exactly what happens when you skid or skip.