Mace,
That diagram is intriguing, but I can't fully decipher it.
I know that when on the beach, you lower your pressure for traction in the sand. NASCAR drivers like to keep their tire pressure as low as possible for traction, and they ride off camber in the corners. ATV tires are low pressure to help roll over the terrain.
I understand higher pressure for riding on pavement, or when using the FEL.
If both rear tires have low pressure wouldn't both tires mold to the surface relative to the amount of added weight. Lesser for the high side tire, more on the low, but still overall good for better traction and stability?