30 psi in smooth fat bike tires like
VoodooSix is using doesn't ride all that poorly. In fact, it helps tremendously with self-steer. I have a pair of Vee Speedsters (26x3.5) that I sometimes run on a Pugsley and anything less than about 20 psi creates so much self-steer, the bike is almost unrideable. 10-15 psi means you're truly fighting against the handlebar in a turn. They really smooth out at about 23-25 psi. Because it's a steel frame Surly, there's definitely some suspension in the frame and the ride is not unpleasant. The higher pressures make it possible to ride the bike with those tires.
The Speedsters have an inflation range of 8-30 psi, so their minimum is higher than some would ever inflate a snow tire or a knobby on a fatty. I think it's really all about putting the right amount of air in a specific tire with a specific purpose in mind. Blanket statements rarely work for every situation.
