I was recently on a trip at 5,000 feet with a bunch of people I don't know well, all of whom swore that water "takes longer to boil" at higher altitudes. I'm pretty sure they were confusing boiling time with cooking time (which is longer for boiled foods at altitude because the boiling point of water is lower there).
My offered suggestions (stronger stoves at home, weaker stoves in vacation rentals; more leisure to watch the pot leading to perception of longer boiling) were rejected out of hand.
Boiling time should be shorter at altitude because the boiling point is lower, right? But is there any sense in which my travel buddies might be right? Is there any effect of altitude on the rate of heating of the water?