I'm sure you've already seen it. I learned by using the second method on this page:
http://www.Layhands.com/Knots/Knots_SingleLoops.htm#DoubleDragon
Yes, as you know, I've seen it -- hence my comment:
"I've yet to see a clean, memorable way to tie a Double Dragon after putting the rope through or around an object."
If people want to see this end loop used, a better method needs to be devised. I'm just not very optimistic about finding such a method.