X1's exclaimed "nope" can be discarded to the pile of his others; "yep" is fine,
but high loads and various conditions leave the judgement to one of tools and forces for untying --"YMMV".
The knot shown at the pictures I have shown, is not "yep, fine"...
Noting that that image shows the tail on the opposite
side from what I've recommended --and when, e.g.,
tying to an
eye, whose legs are both loaded, one should
*model* a leg-free bight by putting such slack into
the side first drawn by the SPart--,
I'm a little surprised that you don't find enough
ability to loosen the SPart-side eye leg,
for I'd expect the collaring bight to not be drawn
so tightly given the SPart's nip of it; but you do say
"bouncing", and that can do the tightening! (And
this way isn't what I see as the knot's "forcible
loosening" avenue, anyway.)
I do not believe that there is an objective way we can tell if one knot jams or not;
but I was under the impression that, when we are forced to use tools to untie it
--any tools--, we are talking about a jammed knot.
Well, I see "jammed" in a couple senses. The first is
that the knot will stay tied when slack, which can be
a highly desired atrtribute; this need not exclude there
being a method for untying the knot, reliably. THIS
knot's corresponding end-2-end knot I believe fits
this criterion pretty well, with some vagaries per
material(s) and forces. And then there is the sense
of "welded", where tools and maybe not even tools
only can untie it. (I recall being happy to find that
I could fit the fairly pointed tip of a pulley hook into
a part of a knot and use the 5:1 MA to haul it loose!)
There is some merit to being able to at least untie
using tools, maybe in a not so difficult manner,
but mostly to get one's man-sized force up to the
rope-sized forces (think, large lines). --as contrasted
with the rather hopeless cases of "jammed".
I had loaded the knot shown in the pictures ( tied on the same 8mm cord
I had tied the previously presented one ) with my weight,
and submitted it to 8 bounces / jumps;
then, to untie it, I was forced to use a pencil as a marlinspike.
--a
pencil qua marlinespike??!!! Wow, that
sounds quite feeble! * * S N A P * *
I'll later give this a try with relatively frictive (age)
7mm kernmantle, whose smoothness should enable
fairly severe tightening, yet whose frictiveness impede
the movement I hope to see. AND, to show that I'm
not so confident of success, my pulley will be applied
deliberately at lower effect first, and only increase if
successful.
Still, I think that for many applications, one can already
see utility in the end-2-end version, where the main
goal is slack-security. (In my pocket, this knot qua
bight-hitch in 3/16" silky flexible nylon solid braid
regularly loosens tied around thinner binding cord
--essentially, a knot that is a stopper-ish one tightened
by itself (the binder cord hardly adding much of bulk);
and #1425 joining the ends of the solid braid also
gradually loosens after being set tight.
--dl*
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