Hence the two lines, 4# and 15#. The purpose was to provide a sampling. Any additional lines you'd suggest would be good try.
If lighter lines do not get the loop, then is that because of some reason other than strength?
Of course a doubled over knot would provide more strength, it's no longer a standard non-slip loop any longer. When I tried this the two loops around the eye were not even and it was far too obvious of a knot for the conditions I often fish so I did not mention it. The increase in bulk and visibility was pronounced. However it was quite strong.
Not to sound like a broken record but my point is when you double the jam overhand and improve the clasp component it really beefs up the strength without making the knot bulky and obvious.
Now we're getting somewhere... the case I provided in the other post (striper section) was effectively the jerk test you mention.
I'll repeat - when wading far from shore, to remove a fish waist deep, to hold the fish by the line to put the thumb into the mouth of a striper as the fish thrashes. After a few of these POP went my standard loop knot. Hence I was motivated to seek a better mousetrap.
The 8# pressure theory is hard to swallow. When I have a 38" fish roll back in the Nauset outgoing surf in a storm, or when I hook a fish of that caliber out on Big girl 4 hours into the ebb, or when I hook a slammer blue on a flat and it heads to the channel, or again when I try to thumb a fish while wading - there is a HELL of a lot more than 8# pressure on that knot if you ask me.
In the conditions as you cited, I agree completely. But when the continuum from drag to fly is interrupted by any number of factors the linkage is no longer pertinent; it's at these times that knots are truly tested IMHO.
Frankly the challenging replies only make me more cautious to evalute the idea more thoroughly. Keep em comin'
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