It took us 4 hours to go 3/4 mile because my friend had to stop and sit down about every 30 yards. At 3/4 mile we stopped for about 1.5 hours until he felt he could move again. At this time he was still feeling dizzy, nauseous, and winded.
Symptoms at altitude are altitude sickness until proven otherwise.
Please take the following comments as constructively offered, Harvey
Even a fat, out of shape slug could do 3/4 miles in 4 hrs. Your friend had AMS. This can happen no matter what shape, size, condition a person is. Some are just genetically or otherwise prone to it.
Yes, it is a bummer and in 17 trips to the Sierras I have had to alter/change/stop/quit usually because others had AMS. I'm usually immune but have had it myself at 10,000 ft (and stopped) and at 19,000 ft elsewhere (and stopped 2 days). I have also evacuated very ill AMS/HAPE/HACE victims. Before placing all the blame on the patient, I'd suggest a little homework on AMS.
Here's an excerpt:
Anyone who goes to altitude can get AMS. It is primarily related to individual physiology (genetics) and the rate of ascent; there is no significant effect of age, gender, physical fitness, or previous altitude experience. Some people acclimatize quickly, and can ascend rapidly; others acclimatize slowly and have trouble staying well even on a slow ascent. There are factors that we don't understand; the same person may get AMS on one trip and not another despite an identical ascent itinerary. Unfortunately, no way has been found to predict who is likely to get sick at altitude.
It is remarkable how many people mistakenly believe that a headache at altitude is "normal"; it is not. Denial is also common - be willing to admit that you have altitude illness, that's the first step to staying out of trouble.
It is OK to get altitude illness, it can happen to anyone. It is not OK to die from it. With the information in this tutorial, you should be able to avoid the severe, life-threatening forms of altitude illness.
Full tutorial at:
http://www.ismmed.org/np_altitude_tutorial.htm