I’m sort of a fan of soft shackles but but I also like to wonder about things, so I wondered if the knot could be replaced with a toggle and of course the sailing community is way ahead of me. LINK
I whipped one up just to play with and I like it, I wouldn't hang from it obviously (it's 2.2 lash-it) and I'd make the eye a bit larger next time so that I might be able to operate it one handed, but it wasn't bad to make and you don't have to tie a knot but you do have to splice.
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