Freshly graded roads are notorious for ruining tires. If your going to be running at normal road speeds 25-50 mph reduced pressure would be a bad thing, it wont help much to reduce damage at those speed and will reduce your control. They air down for rock crawling but speeds rarely exceed 5mph. the best way to reduce the damage is slow down, it will get better in a week or so.
_________________________
Depend on yourself, help those who are not able, and teach those that are.