I tried and extra round turn (3 instead of 2) in the loop of the tautline, for instance, and it holds better. Is that considered best practice, to break with tradition, or might I just have the wrong knot?
It's perhaps a fallacy of inheriting practices from
a time when materials were more similar --both
in surface friction and strength (per-size demands
were less).
The
Blake's hitch (aka "ProhGrip" per me) was introduced
prior to Jason Blake's intro by Heinz Prohaska, and for it
he commented that for any ropes in which the hitch
seemed not to hold well on account of stiffness,
add an extra turn
around the tucked tail;
but if slippage seemed to come from slipperiness,
to put extra turns in the single-strand-wrapping
*half*. In short, he recognized that different ropes
might have different behaviors and that the knot
should be adjusted --as you have also realized.
Sometimes rather than adding a wrap in the hitch,
I *guard* the hitch with a half-hitch or full round turn
leading to the hitch --of course, one needs space for
this in what you're tying to. These added turns will
take the full force, and are in a sense *tied off* by
the complete hitch they guard.
There is also the consideration of the particular form
of the wraps : i.e., it has been recommended that for
hitching onto rope (vs. a solid/rigid object) the version
in which the successive turn(s) is jammed between the
SPart and initial turn will hold better, more inclined to
put a bend in the line. YMMV. Of course, you could so
form the "guard" structure but use the non-jammed
full hitch behind it.
--dl*
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