My evidence is in 3 parts:
1. Its my cognitive thought processes - forming a view - with considered evaluation of the core gripping mechanism of a Sheet bend core in comparison to a Sheepshank. These structures I then compared these structure with a Bowline and how that core functions.
2. It narrows (rather than w-i-d-e-n-s) the definition of a 'nipping loop' [yes, this argument is tenuous but still has some merit]
Mark, are you confident that 1. and 2. constitute evidence that a nipping loop must be loaded at both ends?
Are you saying that your definition requires the term 'Nipping Loop' to include the requirement for both ends to be loaded, or are you holding that a nipping loop cannot 'nip' if it is only loaded one end (the second end clamped)?
In
l00king at a somewhat-corresponding
sheet bend--or, using the similar, wrongly derided
"left-handed bowline"--,
the opposite-sided version will produce a more *rounded*
turNip(of the end-2-end knot),
which while not changing the base of this argument,
does give an
image that swings in Derek's favor.
Either way, you are going to need to address the situation of a Bowline with one leg trapped and loaded 100% which can lead to a turNip performing (nipping) correctly while directly loaded only on the SP end. This is still a Bowline performing under one of the extremes it is expected to handle.
Here I quite beg to differ :: How can differently loading
a knot --indeed, going from eye loading to end-2-end
loading (and then there's turNip-only loading, "through
loading")-- at all be reasonably considered,
for knot
theory, dealing with the same knot?! In
practicalcircumstances, one will want to consider possible effects
of usage --perhaps the risk of lowering with a large eye
and snagging the up upon something such that the
lowering S.Part lowers to become untensioned while
the eye knot becomes "ring-loaded" and the knot, in
knot theory terms transforms into an end-2-end knot!
But in shaping definitions, I don't accept that knot classes
are immune to such changed loading profiles; indeed, I
posit that *knot* entails a particular profile.
Alternatively, you are going to have to restrict the range of operations the knot can be subjected to in order for it to qualify as a Bowline. i.e. disqualify the Bowline when it is only loaded on one leg. Personally, I think this would be a silly distinction resorted to only to justify a distorted definition.
Yes, that is what I will do, for
knot theory. When I haul
your
bowline up through some "V" such that the nub abutts
and jams, I'll be loading that knot qua
stopper. (Should I for
some reason be hauling on the tail, I'd have
Ashley's stopperwith one section way loose (the former eye part)!)
So we have, as I've previously remarked, two ways of seeing
"knot", both with good reason to be used, but separable to
different regions of discussion/usage.
3. In my personal view, a nipping loop is a compression element - and therefore, for it to properly function - it should be loaded at both ends. And this is where I draw the line with the core function of a Sheetbend. There is no fully functional compression element because it is only loaded at one end. However, the Sheetbend does have a 'collar-capstan'.
Yes, a nipping loop must be opposing loaded both ends, otherwise an unopposed end would simply respond to load on the other end by following it out of the knot.
BEWARE MIXING THEORY & REALITY/materials :
what you describe is precisely what happens when you
load an agreed-by-all-as-it-is-our-paradigm/basis
BOWLINEin HMPE cord --the "ongoing eye leg" feeds through the
turNip and out ... , collapsing the eye to the object
of resistance, and then going from their, ignominiously!!
SO, did our paradigm knot
bowline just cease to be that,
during/for THIS loading & material?!
THIS is why I move away from behavior to "appearances",
as in, e.g., calling the venerable
two half-hitches & midshipman's
hitch "nooses" (maybe selecting "noose hitch" for the former)
and not "hitch" & "eye knot" ; I don't want my knot to change
classifications per force or material!
And so while I understand and sympathize with Derek's
point about knot physics per "clamped" ~= "loaded both ends",
I move towards what perhaps underlies Mark's point of view;
in my direct terms, I'll say "in favor of *appearances*" --though
that then leads to perhaps equally problematic deliberations!?
(Recall that I --I think(!)-- advanced my
"mirrored bowline"--i.e., that
water-bowline-like-but-with-larkshead-base knot
with "Janus" collaring of the "ongoing eye leg"--
as a case that appeared to have just the sort of nipping turn
(in fact, TWO) Mark insists upon and yet practically more of
the clamped-but-not(much)-loaded such leg, overall --at least
the 2nd/following turNip must take away much force...).
I think that this should be in the *bowline* class, though
it might be pretty shy of Mark's specified loading; it does
though maintain the rounded turNip appearance.)
I can accept a degree of mileage from this perspective, in that if sufficiently abused, the Bowline will morph into a noose. This noose is certainly not a Bowline, and in the transition from clear Bowline to clear noose, there are a continuum of stages when the knot is neither one form, nor the other.
Yes, and the ore so with many of the, what-I-call,
"anti-bowlines" --where the returning eye leg enters
the
turNip from the opposite side of our paradigm:
there is greater tendency towards the turn becoming
more helical, open/extended than round & compressing.
But even the paradigm knot does this, and can go all
the way to that (
"pile hitch..."-)noose structure or be
arrested mid-way, with a decided helix vice
turNip.
THIS is not theory, it's observed results.
--dl*
====
ps : Recall my above question re the
fig.8 base with
a bowlinesque returning-eye-leg collaring (which preserves
much of appearance...) : was that a
turNip in the base
--which resembles the form in the same-side
sheet bend(and which indeed is one of the suggested securing for
that knot --an extension in which the line forms a
fig.8(the U-part/bight left unaltered, though in practice this too
might be given a securing extension, in like-diameter ropes)) ?!