competition knot-- why doesn't it roll?

Here is the competition knot: https://sicgrips.blogspot.com/2021/01/competition-knot.html (thanks for the write up SICgrips!).

Why doesn't it roll over itself like an EDK? Does it? Do you just leave enough tail that it isn't an issue?

Really want to start using this to freak out gym staff and partners, but would like to learn a bit more about its failure modes first. Please don't make me sign up on the IGKT forum, I can't remember any more passwords.

Ok I can answer my own question after playing with some cord. There are two forms of the knot, depending on which side of the standing end you reeve the working end along. If tied as in the link, the knot doesn't roll because the other side if the loop is on the outside of the knot and is under tension. If tied in the other orientation, the knot has more tendency to roll, because the outside strand is under less tension. 

Looks like a water knot, but just tied with a rope instead of nylon webbing. Makes sense to me why it works, but I'll just stick with a nicely dressed figure 8.

I've been using this knot for maybe ten years. 

If dressed neatly, I find it unties much more easily than a similarly weighted figure 8.

IIRC, a manager at one of the local gyms showed it to me.

Even so, when a front desk worker caught me using it, she made me switch to an 8, despite my pleas that "X" showed it to me.

Fortunately, it takes a close look to recognize, so once she went back to the desk...

Bump to hear more experiences with this knot. I read about it on one of the endless figure 8 v. bowline threads and was intrigued enough to try it in the gym the other night. I like it, but I'm not ready to fully embrace it yet, I'd love to hear about good and bad experiences.

This knot is fantastic y'all. It proves you have a large dong to use it, because you are bold and your partner will be fraid' like mebbe you're a falling faster than a one legged man in an ass kickin contest.

Still using it and I’m not dead yet

Mark E Dixon wrote:

I've been using this knot for maybe ten years. 

If dressed neatly, I find it unties much more easily than a similarly weighted figure 8.

IIRC, a manager at one of the local gyms showed it to me.

Even so, when a front desk worker caught me using it, she made me switch to an 8, despite my pleas that "X" showed it to me.

Fortunately, it takes a close look to recognize, so once she went back to the desk...

NB : The Fig.8 eye knot can be tied similarly.  I found such a knot some pre-aughts age, and it made copy at least in "John Shaw"'s (actually Budworth) book on knots.  The loading on these knots is substantially different then the similar, "offset" end joints, so rolling is unlikely.  In both cases, the main strand loaded should run *interior* to its twin strand.

*kN*

knudeNoggin wrote:

NB : The Fig.8 eye knot can be tied similarly.  I found such a knot some pre-aughts age, and it made copy at least in "John Shaw"'s (actually Budworth) book on knots.  The loading on these knots is substantially different then the similar, "offset" end joints, so rolling is unlikely.  In both cases, the main strand loaded should run *interior* to its twin strand.

*kN*

Ok, that's good to know. Is it just more stable? I'll play with it later and see if I can understand why.

Can report back that I have used the competition knot several times since the OP and I'm also not dead yet, although I don't think I've taken any lead falls on it yet.

JC,
This is merely one of the corresponding eye knots to #1412 Water knot (aka Ring bend / Tape knot).
All end-to-end joining knots have 4 corresponding eye knots (within a chiral domain).
The knot you depicted isn't 'offset' - so it isn't vulnerable to capsizing in the same way as #1410 Offset overhand bend (aka 'EDK').
I've attached a photo of the #1411 F8 bend and its 4 corresponding eye knots (per knudeNoggin).
...
There is also a remarkable corresponding eye knot to the #1053 derived Butterfly bend.(the Mobius Butterfly eye knot). The 'Butterfly' derived eye knots are interesting to examine...

I get that it isn't loaded exactly the same as an offset overhand bend, but the only difference is that one more strand is loaded, so the same loading scenario is present, just with one more stand in play. When you pull on the standing end, it stresses the knot in a way that makes it look like it *could* be unstable, at least compared to say a rethreaded figure 8 or bowline. I don't hesitate to use the knot, properly dressed and with enough trail, but I like knots and the theory of knots and it seems like a question worth asking.

Mark, very nice diagrams. Do you have any knowledge of whether the knot from the 3rd or 4th row is preferred as a tie in knot? The post above suggests the 3rd row is better, but I'd love to hear any further explanation.

JC,

It isn't the same loading profile.
Refer to my post above - I've added another photo illustrating loading profiles.

Look closely at the 'axis of tension' in both loading profiles.

The core of #1410 ('EDK') is completely offset from the axis of tension.

The core of #1412 derived eye knot isn't offset.

Also, load is injected into the core of the eye knot from 3 vector directions.

In an end-to-end joining knot (ie 'bend') load is injected into the core from 2 vector directions.

...

In reply to your question re "which knot is preferred as a tie-in knot"...

Nobody has conducted any peer reviewed testing using the 'scientific method' with a 'control group'.
However, it appears to me that the tail outside orientation might boost stability - due to a choking effect.

But - this is purely hypothetical - and needs to be tested.

Mark Gommers wrote:

Also, load is injected into the core of the eye knot from 3 vector directions.

In an end-to-end joining knot (ie 'bend') load is injected into the core from 2 vector directions.

Yes, and you seem to be assuming that the third loaded strand prevents rolling, without giving any attempt at an explanation. It isn't as obviously stable as other tie in knots, so I'm approaching with skepticism in the hope of learning more. Given the dearth of peer reviewed papers, you seem very certain of yourself. 

J C wrote:

If tied as in the link, the knot doesn't roll because the other side if the loop is on the outside of the knot and is under tension. If tied in the other orientation, the knot has more tendency to roll, because the outside strand is under less tension. 

So is the hypothesis that the sicgrips page shows the superior (tail-inside) dressing but the 2 youtube videos linked from it show the inferior (tail-outside) dressing ?