I didn't have time to watch the vid but the grinner is normally referred to as a uni, and the double grinner is a back to back uni. Pretty solid knots, though not my favorite line to leader knot.
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Duncan (Uni) Knot Details Names: The Duncan Knot is named after its inventor Norman Duncan and is also known as the
"Grinner Knot". It was also popularized under the name
Uni Knot by Vic Dunaway as a versatile knot which can be adapted to many purposes including snelling; joining two lines; and connecting hooks, swivels and lures with a loop. It is described as being the same as the Hangman's Noose.
The Knot the chap does in the video is not the Grinner knot as we know it.
What he does is do a number of wraps down the line, then ties a Uni Knot over that, then same on the other side...
Complete mission compared to the 7 turn Uni-Fig 8.
