I was more interested in why Rob Chisnall liked to use it in anchoring applications.
It seems as though it might be placed between
the Tensionless Hitch with the 3 wrap prusik plus carabiner,
and the simpler version using the strangled double overhand knot.
I've not checked details to what you refer re anchoring, [1]
but one potential issue with the
tensionless h. is that
of rotational force on the object, which the simple non-knotting
of the basic version won't address. By using a gripping
hitch on the tail, one thereby does *violate* the "tensionless"
aspect --which only makes sense in reference to the tail--
by giving tension to it. The tail's tension though will likely
not need to be fully equal that of the SPart, in preventing
rotation --otherwise, it's there to arrest it.
(I don't know of any studies on this issue.)
[1] Okay, reading Mark's paper, I see his two tie-off
methods. I suggest to these that one might simply
make a turn around the TH's SPart running back
around to then tie off w/
2 half-hitches (
clove)
where the finish is with a
slip-knot (i.e., this
would serve qua stopper against the 2nd HH
and the slipping tail would undo both stopper
& 2nd HH if pulled).
With stiff rope, one can find some things not so
easily done. Mark thus shows flexible thinner
rope with the
Prusik h. coming to the rescue
for the stiffer main rope. (The knotted 'biner
might be omitted for a
sheet bend variant,
to spare resources.
--dl*
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