Two co-workers are climbers. One recently told me that she ties-in
to a safety line with a simple bowline.
I am currently trying to convince her that this is a bad idea.
AMEN! --re "bad idea".
But you needn't combine all that you have;
choose one or the other finish.
Mark ends up recommending Fig 26, which has a Yosemite finish.
Mark is evidently in heat for that finish --he throws it in
EVERYwhere, royally mucking up my lovely
"EBDB" even!

Your (rock)climbers should be happy with either of
#s28-9 /
30-1.On these, one could put on a 2nd collar around the SPart,
sending the tail ("rabbit") one more time "down the hole",
thereby having the tail pointing towards the eye (should
that be desired).
The forms shown --i.e., with a single nipping SPart loop-- will
be more quickly tied than the "double" knot you started with.
The double turn can improve slack-security, or lessen the
loosening (which in the knots above shouldn't be much).
Note that the collar around the one eye leg can/should be
set tighter than that around the SPart, a little bit. And by
holding this eye leg in this way, the central nipping loop
should not overly loosen.
The
EBDB should have it's tail loop set fairly hard,
which in the compound knot you present above isn't
so easily done (as, on putting in this loop, one has yet
a further central tucking to do --viz., the eye-leg collar's).
--dl*
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