Just ran some more tests.
Loop on each end, 12# maxima two pens same model, pulling to break point.
The surgeon's loop (which I never use) did break when not seated right. Scratch that knot it's too hard to seat right and no one uses it for flies anyway.
But even the uni-style double jam loop always held over the standard non-slip loop which popped at the clinch every time out of 5 tries.
The nail style double jam loop broke the uni.
The standard loop knot was much weaker than either.
Give it a try for yourself sometime.
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