hikin_jim wrote:...the difference between using your number versus the one I used over a 10,000 foot elevation gain is 4 degrees Fahrenheit, an amount which isn't going to have a huge impact on the operation of a stove.

When on the edge of acceptable stove function I think 4 degrees matters.

hikin_jim wrote:Pick whatever PSIG one feels is appropriate at sea level, and one should have that same PSIG at 10,000' in temperatures that are 20 Fahrenheit degrees colder.

Jim, it doesn't scale that way. The P-T curve is logarithmic. As the temperature drops the pressure differential narrows so you won't get the same fuel flow rate.

edit: Here's a chart to illustrate. You can see that at sea level and 20° a full canister is at about 13 psig whereas at 10,000 feet and 0° it's at about 8 psig. To get the same pressure at 10,000 feet the fuel temperature would have to be about 10°, not zero.

hikin_jim wrote:In addition, I can work with 2 in my head, and it's easy to remember. It's a rule of thumb not a precise calculation.

So then make it 1° per 1000 feet. It's no less precise and the arithmetic is even easier. Since your rule is mostly for beginners, don't you think it's wiser to err on the conservative side instead of being overly optimistic?