Got any example videos?
My first guess would be a bowline:
but it takes longer to tie than just wrapping the rope around your hand a couple of times and hanging on to it. Besides, you'll hurt your hand long before the rope slips!
I use a mongrel variant of the clove-hitch around my UJ connector, and just bring the loose end back underneath rather than threading it through under the cross over. Works beautifully, and there are no parts to leave behind, and no skin lost off the hands.
Ezzy has a special knot too.. I think he shows it in some of his rigging guide videos?