RChung

Size of contact patch doesn't actually have much to do with rolling resistance. Rolling resistance depends much more on frictional losses in other parts of the tire/tube system. It's sort of sleight-of-hand misdirection -- people looked at the tire and thought the losses were related to the contact patch, which they could see since it touches the road; however, most of the losses occur in the parts of the tire that they weren't looking at. That's why latex tubes reduce rolling resistance compared to butyl tubes, even though they don't affect contact patch; and why two tires with the same width and same contact patch but different sidewalls or rubber thicknesses can have different rolling resistance. It's also why knobbed tires can have higher rolling resistance than smooth tires even though their contact patch is smaller.

When you understand that it's not the contact patch per se that matters, it frees you up to look at other components of the system and why lower tire pressure can, in some but not all cases, reduce rolling resistance even though it can increase contact patch. That is, in the same tire, higher pressure will not always run faster.