Dying on Everest isn't a matter of sensibility. Most people who die are stricken with altitude sickness[1]. HACE and HAPE move fast, and the only effective treatment is reduction in altitude. Hyperbaric chambers can buy time, diamox isn't shown to be effective for HACE and HAPE.
Acute mountain sickness (AMS) can strike even lower. A friend of mine was in Nepal with the Discovery Channel this past Fall. One of the producers was evacuated due to AMS when they were under 6000m. Altitude is a lottery. For my part, there's plenty of climbing near sea level that kicks my butt.
[1] http://news.softpedia.com/news/Leading-Causes-of-Death-In-th...