Taso, I believe I've posted a few articles on this site from Arleigh Reynolds, and he's the man that came up with that by doing his own tests on sled dogs in Alaska. If it's not up on this site, I will find the article and post it for you.

It should be noted also that Gringo has moved on from a lot of what Mayfield told him, and he has been very successful with the dogs he has down in South America at this point.