Recall that the air was pulsing with insects. Many of them wanted my blood. I covered up what I could and reached for the mosquito repellent. Squeeeeeze...squeeeeeeeeeeze...oh no. Seems my DEET had evaporated, or maybe been sabotaged by ninja mosquitoes. Which brings me to
Day two: leave pack behind, hike back to road, shuttlebus back to car, drive to town, get DEET (and grab the pen, spoon, and cup I'd left in the car), have mocha, reverse travel steps--huff, puff--and after ~11 miles arrive back where I started the day (except now it's 80 degrees). Pack up, move a couple miles into trees and call it good.
Camped off trail at the top of a pass, there were no bugs.
The view from camp was nice: the largest Clark Lake due north, backed by peaks along the eastern edge of Yosemite National Park. When the US Cavalry had patrol duty over Yosemite--which then included the Mammoth backcountry I'm traveling through--they came via passes near the right hand peaks. A trail still goes through there, but the famous John Muir and Pacific Crest trails come this way via a pass just left of the leftmost distant peak.
The watering hole wasn't bad looking either.
A friendly family camped in the trees purified water for me with a little Star Trek device that uses UV light to kill possible nasties. The owner had to put on dark glasses to use it. Fascinating what you encounter in the backcountry.