I made a videoclip to show how it behaves: http://www.youtube.com/watch?v=mEFvEiD8ANA
Great video to demonstrate your assertion Inkanyezi.
Okay, this isn't quite the circumstance I had in mind
--this, to a *spar*/*pile*, and I was thinking of an *ring*,
such as on an anchor; and I was only considering the effects
of tensioning, not shifting angle of incidence.
The behavior shown in the video (where it kinda seems like
the upper rope is given more wiggle, hmmmm!

)
is something I've wondered about affecting
knot behavior,
with the cyclical slackening on one leg (maybe only one,
maybe both alternately).
AND, we might conjecture that the movement-from-length
which I pointed to is relatively minor in effect to that of
the shifting of the eye from changes in angle. But do
realize that the video shows angle shift (laterally and also
perhaps vertically --around & along the cylindrical object),
and not pure tension variation.
Around a RING, I don't see same behavior occurring. And
we do have, in the unwrapped eye, the concentration of
pressure to aggravate if not be the primary cause of rope
deterioration.
Thanks,
--dl*
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