I've never done this, but here's an idea: What about riding by night, and resting/sleeping under cover from 8-9 am until an hour or two before sunset? Lots of nocturnal wildlife, fewer heat/sunstroke/hydration issues, plus you'd catch every sunrise, sunset, and see some killer stars. If you planned your trip around the full moon, it could be amazing.
Of course you'd need to find rocks or other shade, or bring some kind of "sun fly" (as opposed to rain fly) for your tent. Sleeping when it's light out and hot would suck, and you'd have to have a good lighting system and lots of batteries (solar recharger, too?).
Anybody ever try this?