I don't know how you can disagree, that a chord with a tritone is not dominant or leading tone. A tritone can occupy a I's postion, but it's still a dominant function. I don't get it. Roughly, 400 years of theory AND practice proves it. Without the tritone, in our present system, music will not and could not move.
A lie goes around the world before the truth gets it's shoes on. (Mark Twain)