I humbly consider myself a bit of a lonely pioneer in this field, in the U.S. anyway. In 1986, I think, I installed a set of factory Toyota split rims (16x6) on my FJ40, along with BFG All-Terrains in 235/85R16--a VERY rare commodity then. This was after reading many accounts of expedition work in Africa and Austrailia, where skinny Michelin XS 7.50x16 tires seemed to be the standard. All my friends had 33x12.5s stuffed into their wheels wells, and laughed at my bicycle tires. When it developed that I could go anywhere they could, with obviously less strain on steering and suspension and biceps, they changed their minds.
The split rims didn't work out for this country, because tires here are not made for tubes (which I found out the hard way after two catasrophic tire failures). But I never abandoned the narrow tire concept, and now run 255/85/16 BFG Mud Terrains. It took Scott to elucidate so clearly why narrow tires work so well.
In Africa the universal standard is still a 7.50x16 tube-type tire on split rims, often manufactured in Africa. Firestone makes a 10-ply tire in Kenya that is nearly indestructible; I've also seen BFGs and Dunlops, among others. Not many fancy tread patterns, just simple lugs. Wide tires are almost vanishingly rare except in cities.
A mechanic I know there related a long remote drive during which he suffered two flats, using up both spares. He dismounted one tire and stuffed it with grass, giving it enough shape to reach the next village. The tire was destroyed by then, but he saved himself a 40-mile walk through hyena country at night.
So, another advantage to narrow tires: It takes less grass to stuff one!