Well, I find that I cannot answer that question, because I do not know what a T-bend is.
It's a supposed attachment of a line to another, mid-span, so to speak; the attached line makes
the bight part and the other line forms the gooseneck mid-line to receive that bight.
(It is more stable if one forms a bight collar on both sides of the mid-line loop.)
--have only seen this mentioned in CWarner's
A Fresh Approach to Knotting & Ropework.
There is some significant difference in geometry among these
It triggered an initial Bol****s, but by the time of the third read through, again I am in agreement
that the Bk,Blt is a nasty knot for shape changing under tension and that different usage configurations
lead to different usage geometries.
Odd reaction, and to what you must have known, anyway. What most bothers me, of the
changes, is the Lapp Bend's hauling of what would be one of the Sheet Bend's SParts back
sharply (as here it's an end). And yet even this is less distortion to the
nub/knot than what
topological manipulation will do to a Bowline--though for that, it's required to connect the knot's
ends in some way. Ashley's Stopper is one knot that can be topo-fiddled from the Bwl.
And then you catch my attention !! it will be more easy to assess geometry and component
features (such as the "gooseneck" of the Bowline,
OK, Show me !! Take the Bk,Blt of the first OI example. Show me how to catalogue its 30 odd variants using geometry and component features. I don't understand what your subsequent words mean so please show me more clearly in a manner that I can apply.
But this
geometry (shape)-based method will give a different sort of classification.
I.e., it won't take the bight-loop
knot-nub (I'm thinking that maybe the term
tanglemight work well for this afunctional view of the structure?!) and unite all manner of functional
knots that arise from it, but rather will group together those knots that resemble it geometrically,
which implies functionally, and which shows that more than the
tangle is the classification guide.
A paradigm for my thinking is the Bowline, whose essence I regard as its central nipping
loop--the so-called "gooseneck". That DoubleCross loopknot from Dave also has such a structure,
and the end reenters this loop on the same side as for the Bowline, so I might put them together.
"Anti-Bowline" knots I see (in the sense of "anticyclone" "anti") as similar but with the end entering
from the opposite side, as for the "Bollard loop" of issue a few KMs ago. And all these (loopknots)
stand in contrast to e.g. the trace knots Overhand & Fig.8 loopknots, and various Overhand-based
knots, among others. Although for the bowlines & antibowlines there is some issue with the very
loop that characterizes them: by degrees of dressing/setting and tension, it can deform into
more of a
spiral (the Bowline can e.g. capsize into a sort of dog-leg S & Pile Hitch'd end).
And, yes, there is much subjectivity in such discriminations. --much like biological classification!?
And there are all sorts of challenging combinations of knot characteristics to sort out.
(What does one do with the feathered animal with mammary glands and an exoskeleton?
--besides send it back to Australia!

)
--dl*
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