Originally Posted by
Wildwood
The article referenced was measuring 23s vs 25s, unless I missed the paragraph you intended. This discussion was started as 38mm tires on a Lemond Buenos Aires that underwent a conversion to 650b to fit fat tires. Mtb tires and city bike tires have more rolling resistance than road bike tires. Unless I am uninformed (not the first time).
the article and many others like it talk about the principle - it isn't the width of the tire that determines rolling resistance, thus other things being equal a wide tire doesn't offer more resistance than a similar narrow tire. They deform differently but end up with similar total area of footprint. Other things tend not to be equal, tires and wheels weight more, fat tires are often knobby, etc.,