Theres that split second mistake you were talking about......could very well have broken your neck!! 
Well I was being stupid.
I was bombing down a steep hill at about 35 mph and lost control.
Bicycleing is very, very safe if you just control your downhill speed.
I see your point though. Every sport carries SOME risk. Even walking down the street carries a risk. The question is, how much?
And powerlifting is a lot more risky than most other sports.