But wait a minute - isn't the contact patch a constant?
Been reading this thread as I want to try narrower next year as well.
But one thing still bothers me about a bit of the discussion and Scott's article. It's argued that narrower tires will perform better since the contact patch is smaller and presents more PSI to the terrain.
If two tires are inflated to identical PSI, let's say 15 PSI. And the vehicle weighs 5000 pounds, then each tire is called upon to carry 1250 pounds weight, and therefore the contact patch is a constant 1250/15 = 83.33 square inches. I can see how the shape of the contact patch can matter, depending on the terrain - but 83 square inches is a constant, no matter the aspect ratio of the tire. The narrow tire can't PUSH the ground any harder than its internal pressure will let it.
Maybe the benefit is in a second order effect like the sidewall flex? Or a dynamic benefit that depends on how fast the tread recovers after it rolls over the surface?