To be a little more serious than my previous post; I have ridden with and without safety protection (helmet, gloves [mtb type]) about equal times in my life so about 25 yrs with, and 25 yrs w/o; and during those time frames given the types of mishaps (due to my own fault, other riders, vehicles, and/or weather, etc.) I have experienced, it would not have made much difference in the long run regardless of speed since it was mostly dictated by when and where the incident occurred.
I have been completely blow off a road by the wind before, but luckily no ravine or cliff drop off when it happened; nor wall/pole etc. to run into. A truck knocked me off a road in a race (where did it come from? An unmonitored side street!), but again same outcome as above. My fastest speeds were in my teens when riding down my local "hill" without care or concern; but I did that same descent a couple years ago and almost went off the side of the mountain at a much lower speed, but at a much higher level of uncomfort trying to relive my junior years while having notably worsened eyesight, reduced reaction to the conditions, and obvious reduction in skill which is perishable over time.
Never at any time was I pressured by the thought of glory, wealth, and/or peer pressure (though probably trying to impress a girl on an occassion or two!) to do what I did and take the risks I did take and still do. It is all on me! Except that darn "racing truck"!
I have participated in many sports/activities where injuries occurred from odd circumstances that had nothing to do with the perceived danger/risk level of the sport as most would think compared to the cycling, mountain climbing, scuba diving, and more; and yet hospitalization occurred because of the unpredictable irregardless of skill and preparedness.
We will do what we want, or what we feel is necessary at any given moment and we must accept that accidents can occur and their severity is at the fate of many factors which determine what the end result will be.
That being said; please be safe (if you can) so we can continue the discussion/debate tomorrow and for years to come.