Your point about the time it takes for HAPE to set in is valid. But I'm pretty sure that times in the death zone vary greatly. Most parties camp at least one night above 8000m and weather / SNAFU's often hold them there for multiple days So the total time above 8000 varies by much more than the half day it takes to walk down.
No doubt though, the death zone could kill people playing ping pong. Yet the down-climbing problem is global to mountains of any size. The extreme altitude on Everest amplifies it. More accidents occur on the way down on mountains less than half the size of Everest. The mountaineering bible, "Freedom of the Hills" discusses the phenomenon extensively:
No doubt though, the death zone could kill people playing ping pong. Yet the down-climbing problem is global to mountains of any size. The extreme altitude on Everest amplifies it. More accidents occur on the way down on mountains less than half the size of Everest. The mountaineering bible, "Freedom of the Hills" discusses the phenomenon extensively:
http://www.amazon.com/Mountaineering-Freedom-Hills-Mountaine...