Steven,

I agree. However, it one is in good health, don't smoke, go through
the IMSAFE checklist before every flight, hypoxia risk at low altitudes
should be quite minimum. BTW, for us, the E part is very important ;-)
we always pack plenty of food and water for any flights short or long.

It's the same issue with the risk of getting the bend while diving.
I had witnessed two cases of so-called 'undeserved hit' where the
divers did not violate any safety rules and did not do any
decompression dives. In one case, the diver was on a diet (on a
liveaboard with 5 dives a day) and had a sunbath right after a dive.
Another case, the guy stayed up late bar hopping the night before.
Both divers had sophisticated dive computers monitoring their N2 levels
etc.. but good equipment can't help with poor health condition.

Hai Longworth