We were at the Mod Nats, and watched in amazement as they literally poured 50-pound bags (in the plural) of sugar on the track, added a small amount of water, and let it sit overnight. While this process would yield some improvement for a while on the clay tracks we're used to here in the midwest, it would be followed by a sticky mess. But the desert sand they have to work with in Albuquerque responded well to this treatment.
In fact, the track got packed so hard it was like racing on concrete, and tires would go from new to partly bald in one battery pack and would be junk after two. While it is probably exactly what the ARCOR folks need to do with their dirt to make a consistant racing surface, I suggest you try it on a small part of your track and see what happens before you do the whole thing.
Some tracks around here will occasionally spray on liquid calcium chloride to increase traction and reduce dust, but mostly we simply learn how and when to water and the traction and dust reach a happy medium. After all, this IS off-road!!
Engineering Without Fear