looks like a quick release/slip version.
However, the fact that the "toggle" is made by two lines, not only one, means that it is stiffer, and it is more difficult to be dragged and "swallowed" into the nipping turn.
Actually, we should be chary of such things (even
by some
per se analysis --backed by experience):
to expect some
toggle action requires that there
is slippage in the turNip of otherwise gripped parts!
I have done things like this, which from on perspective
seemed attractive, but then the nipping-gripping effect
of the turNip frustrated the hoped-for pressure to secure
the toggle. (And, e.g., in some fiddlings to find some
slip-free hitch, there have been cases where I had the
turNip and it proved too tenacious and impeded the
spilling that was wanted, holding like a
sheepshank.)
E.g., one can use a structure just like the
sheepshankwith that bight-end only
beside and not collaring
the SPart, and do the collaring with a like-above wrapping
of the tail (around SPart & through bight end, which is
passed through the turNip), but then that turNip grip
proves at least a little problematic in getting the sort
of strong bight-down-upon-tail-wraps effect that's wanted!
--dl*
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