What would you consider to be a true test of an efficient smoker? I have read on a few posts that the Feldon Calculator didn’t necessarily use math to determine some of the formula(s), such as chimney height, but rather compared actually smokers and incorporated their characteristics to make the formula. If this is true what made these smokers and their smoke stacks good enough to be used? Is there a standard for fuel efficiency that all smokers should be compared to? I think it would be interesting if there were a test that we all could do on our smokers to not only compare them to but, if shared, would also help builders to determine how to make a better mouse trap so to speak. Thoughts?