Thanks.
It's the middle structure that so appeals to me.
I can imagine a trucker having a set of the stoppered
slings racked and ready for use, if not pre-knotted
(maybe this done better w/clove h. vice girth/ring/cow)
in the lines. Periodically, the user could make slight
adjustments in these slings so to change the point
of abrasion. (Conceivably, in many common materials,
the stopper is unneeded; but it does both help give
stability to the joined structure, and then enables
the separated sling to be racked in storage.)
As for using the klemheist --or any such friction hitch--,
that looks esp. bad : bad knot for larger-tied-to-thinner
rope; and vulnerable to gradual slippage via vibration.
(And, in comparison to the others, more tedious to effect!)
--dl*
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