"tensionless hitch" a misnomer?

[ek]

I've heard a lot of people say that "tensionless hitch" is a misnomer. On his website, Bruce Smith even asserts that it ought to be called "tension-full." (He also refers to it in the title as "frictionless hitch" which is a contradiction in terms.)

When I was taught the tensionless hitch, I was taught that it's called that because the knot (or whatever other tie-off you use to secure it) is not (or should not be) under tension. Everyone I've heard disparaging the term "tensionless hitch" seems to have other ideas about why it's called "tensionless." But the knot is indeed not under significant tension, so it seems to me that the term "tensionless hitch" is a perfectly good one. Furthermore, since there are plenty of situations where a tensionless hitch is not higher-strength than rigging with a knot, it seems to me that "tensionless hitch" is enormously more correct of a term than "high strength tie-off."

Am I wrong?

[gdstorrick]

Post deleted.

[snoboy]

Furthermore, since there are plenty of situations where a tensionless hitch is not higher-strength than rigging with a knot, it seems to me that "tensionless hitch" is enormously more correct of a term than "high strength tie-off."

Curious to see a good example to support this statement.

[NZcaver]

Eliah - are the voices in your head thinking too much again?

I still like the original name I heard for this contraption, back in New Zealand a couple of decades ago. They call it a "no-knot."

[Marduke]

Furthermore, since there are plenty of situations where a tensionless hitch is not higher-strength than rigging with a knot, it seems to me that "tensionless hitch" is enormously more correct of a term than "high strength tie-off."

Curious to see a good example to support this statement.

Easy, a bad redirect or sharp lip will drastically weaken the rope. Rigging to too small of a tree also comes to mind.

[ek]

Furthermore, since there are plenty of situations where a tensionless hitch is not higher-strength than rigging with a knot, it seems to me that "tensionless hitch" is enormously more correct of a term than "high strength tie-off."

Curious to see a good example to support this statement.

Anytime you tie in with a knot at the other end (or the middle), or attach an ascender to the rope, or a descender. Anytime the rope goes over an edge sufficient to reduce the strength as much as or more than a knot would (and my understanding is that just about any acute edge, even with a pad, is a good contender for that). Anytime the object you're rigging around itself contains such an edge, or is inadequately thick (4", I've heard people say) that the bend of the rope around it doesn't result in strength loss. Anytime the direction of pull changes later and the hitch is no longer "tensionless", and anytime the hitch is not dressed properly (so that the rope pinches itself down into the anchor point).

There are many reasons to rig with a tensionless hitch. Strength is very rarely one of them. When you're sending the rope down into a pit for rappelling and ascending, a tensionless hitch never gives a significant strength benefit over rigging with a knot in tension. (For example, an 11mm nylon rope is usually about 30 kN strong without a knot, so assuming 1/3 strength loss with the knot, 20 kN. Petzl ascenders will cut an 11mm rope at between 4 and 6 kN. An unlocked descender will slip down the rope, and a tied-off descender is a knot, and should reduce the rope by about the same amount of strength as the rigging knot.) As far as I know, highlines are the only application where tensionless hitches are actually used because they are stronger than knots.

As for the question of why I'm bringing this up, there are two reasons. The first is that for years when I have said "tensionless hitch" people have objected, without ever explaining their reasoning. Their objections weren't very strenuous, and nobody really cared, so I ignored it. But I'm interested in why people think I shouldn't use that term.

The second reason is that I am involved in training people for vertical caving, and if the use of the term "tensionless hitch" really is somehow counterproductive or otherwise sub-optimal, it would be good for me to recognize that and stop using it, at least when teaching.

[snoboy]

OK, so the examples you give are all good, but they do not demonstrate that the HSTO is less strong than rigging with a knot, just that you need to keep the rigging clear of other things that will weaken the rope... The hitch is self is still high strength.

I personally use it for two reasons:

1 - highline rigging - and there I make certain that there is no where else that the rope strength is compromised.
2 - Quick and low gear usage tie off... Don't care that it is high strength there.

[ek]

I certainly don't mean to say that a tensionless hitch is any weaker than rigging with a knot. A tensionless hitch is at least as good as a knot in most ways that matter, and better in many, which is why I use it often. I just don't think of strength as a big consideration.

If the object you're tying around has too small a diameter, or is sharp, then indeed a tensionless hitch is, in the hitch, no stronger than a knot. But you're right that the other examples given pertain to the rigging as a whole and not to the tensionless hitch specifically.

[gdstorrick]

Post deleted.

[NZcaver]

So Eliah, how come we didn't see you at convention last week? Syracuse is virtually right next door to Vermont.

We could have had deep and meaningful discussions about this and other subjects around the campfire. I can assure you Gary is just as entertaining in person as he is on line. And he doesn't bite - much.

[ek]

So much to do in the summer, so little time...

I was in Vermont shortly before the convention, and did a smidgen of caving...but during the convention, I was visiting some friends in Long Island.

I hope to see you all at another caving event. Though I warn you--I might be caving, rather than initiating discussions about the names of things.

[snoboy]

If the object you're tying around has too small a diameter, or is sharp, then indeed a tensionless hitch is, in the hitch, no stronger than a knot.

I would argue that a hitch as described is not a HSTO or tensionless hitch, just like a mistied bowline, isn't a bowline... Of course we are getting into semantics here, but that's what we are here for - isn't it???

[ek]

No, that's not a matter of semantics at all. Whether or not two rigged situations are the same technique may be a pedantic question in some cases, but it is not a semantic one.

Also, without intending offense: It's sort of absurd to say that it's a tensionless hitch when the tree is 4" wide, but not a tensionless hitch when the tree is 3" wide. It's a tensionless hitch in both cases, and it's perfectly acceptable in both cases. (Though a 3" tree may or may not be adequate for the application at hand, perhaps depending on whether or not it's the only anchor point being rigged to. The 4" tree might not be adequate either.) An adequately strong 1" wide object can perfectly well be rigged around with a tensionless hitch. Doing so will reduce the strength of the rope by a small amount, but so what? There's probably no other practical way to rig to it that's stronger, anyway (if that margin of strength really were an issue, which as I think we've all agreed, it nearly always--and when rigging pit ropes, always--isn't).

[karst97]

I've always heard it referred to as a high-strength tie-off... Seems more appropriate.

[Tim White]

Going back to 1980 I find in the book Wilderness Search and Rescue by Tim Setnicka the term “tensionless anchor”. He does credit to that style of rigging to cavers. I'm sure if one looks, the term is likely much older.

Is this a hitch? According to the Morrow Guide to Knots “hitches are used for tying a rope to another object” and is a knot “formed with simple turns”. Sounds right to me.

Is it tensionless? Well as it has been said, there is no tension on the knot securing the end to the mainline.

What is the issue here? I see none.

As for the term High-Strength Tie Off (HSTO) my first introduction to that term was from Bruce Smith. It appears in print in the 1996 Revised Edition of On Rope.