If you're doing a one-day Half Dome assault from the Glacier Point trailhead, it pays to start before daybreak,
so that it's too dark to see how many parsecs away Half Dome is when you start, and so you can get back to the Glacier Point
vista before dark to spend a few minutes admiring just how far you've gone
and reassuring concerned sightseers that you don't always limp like this (or smell like this either,
for that matter). You'll also be happier if you can get
back to Glacier Point before the cafeteria/snack shop closes - usually by 7 p.m. in the summertime. Otherwise your stomach
will have to wait out the 25-mile drive to Yosemite Valley.