Thank you, knot4u,
Yes, I have replaced the pole with a rope, too. My thoughts are the following:
In the case of a
climbing hitch, there are
many other things that count in its evaluation, besides its gripping power. The matter is complex, and I am by no means qualified to speak about it. Also, due to the obvious dangers an inappropriate hitch can impose on the climber, I dare make no comments, let alone suggestions, for the use of such a hitch for climbing purposes. But we can speak here about the quality of this hitch,for general use.
My opinion is that
no hitch that is based upon nipping wraps around a vertical rope, ( ANY number of such wraps ),
can be more secure than a hitch that involves other, more efficient types of friction mechanisms (2). In particular,
a : the mechanism that involves rope embraces/twists, ( like the one we have in the Reef family of bends, the Surgeon knot, etc.), and/or
b: the mechanism that keeps one "warp yarn" secured into/ in between, the filling/the adjacent "weft yarns", of the fabric. ( More on this last, but not least, mechanism, in a future thread)(2). My post about the 8-nooses (1), was the result of this ongoing investigation on friction hitches around ropes. The fact that the Gleipnir hitch can tighten the two ends of the coiled rope in a most effective way, can not help beyond a certain point. In this case, where we replace the pole with a rope,
the "coil tube" itself can not be sufficiently long - because we can not tighten the two ends of such a soft tube without running the danger of deforming its straight cylindrical shape.
So, I, from my part, have abandoned this class of friction hitches on vertically hang ropes, and I try to device hitches based upon the other friction mechanisms I have hinted above. I suggest that you start a new thread, on climbing hitches and/or
"best hitches around a vertically hanged rope" , for a discussion and comparison of various established and newer solutions to this "ancient" - but always very interesting - knot problem..
Your exposition about the circular-vs-ellipsoid collars was very lucid and helpful for me, indeed. This hitch we are talking about here can be tied in two slightly different variations, the A and the B, shown in the pictures I had posted. Have you tried both of them ? Have you measured any noticeable differences ?
1)
http://igkt.net/sm/index.php?topic=2780.msg16911#msg169112)
http://igkt.net/sm/index.php?topic=2191.msg16938#msg16938