Thanks, Jim! I was going to say the same thing but didn't have time to look up the references.

I also found out that what I was taught in my youth, that acclimatization, once achieved, lasts for many years, is another myth. It certainly doesn't last for 50 years!

This year I'm going into the Wind Rivers from a trailhead at 8,000 feet. The first night's camp will also be at close to 8,000 feet, and none of the succeeding nights will be more than 1,000 feet higher than the preceding night. This is supposed to be an acceptable alternative to climbing high and sleeping low the first few days.

Last year I went in from 9,000 feet and was over 10,000 feet the first night. 3-4-mile days were the best I could do for the first 3 days. After that I was fine. I'll find out if the new routine makes any difference.

While the article itself requires a BPL subscription, the forum replies (free) to the article are quite illuminating and well illustrate Jim's point: Forum replies to article on AMS in SEKI.