Biodiesel should be able to be used under the same loophole that allows electric only vehicles on the road without paying road use taxes. First, it's technically an experimental fuel, and second, when used in pure form, it's an alternative fuel that is not drived from fossil fuel sources. IMO, it should be tax exempt under the same premise as electric cars. Since nobody is dying the stuff red when they're cooking it up in their garages, it would be difficult for any tank dippers to prove on the fly that the fuel was indeed non taxed fuel.

As for mr big mouth, personally, I feel that I have much bigger fish to fry with my own daily problems and foibles to worry about him.

As other's have said. He'll be bragging up to the wrong person one day, and he'll get his due rewards.