What I see is that a common spare donut tire was tested for rolling resistance. I don't believe the test was fair because the donut is not a standard tire - it's definitely got issues (Patrick asked about the spares being "bias-ply instead of radial").
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mcrews: I don't know how long you've been on the internet, or how many forums you've been a part of, but in my experience no one really uses forum search features. Although this one is pretty good being Google integrated, but most forum search codes are crap. Another observation is people who find this forum while doing a regular Google search - yes, they found the site, but maybe the page they found didn't answer their question. Hell, I've done searches on here and found nothing good, mainly because I apparently didn't use the right keywords. I'm not lazy (I appreciate your negative attitude, though), just uninformed as to common search phrases for some things.
If you really wanted to be a productive member of this forum and help, try keeping your attitude to a minimum and just post links to the topics you know about, that others may not have been able to find. Talking down to people here will just make them want to by an H1 Hummer. K?
By the way, at 23.08 MPG, you really don't have much room to discuss eco-anything.