I found this version of a sail-knot which could be cinched with pulling one rope and undone with another. Looks very interesting and possibly can be used for tightening elbow ties (shown on the video below), single-gloves, hand/arm anchoring etc.

I haven’t tried this method yet and will not try in the nearest future, but I wonder if someone has time and space to test it.

I will post drawings later if I find them.

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