http://www.vintagebicyclepress.com/i...64TireTest.pdf Here is another article but I don't think this is where the above conclusion came from. All I can say is it comes from people much smarter than me on the subject.

This is copied from Bicycle Quarterly so all the credit and love should go to the authors and BQ as I was just the copy and paster. If you find this interesting, maybe you should look further into a BQ subscription.