... and everything I've read about the constrictor has said to just cut it off
if it jams since it's nearly impossible to remove otherwise, but ...
That is because Ashely's too-proud assertion has been
parroted as though it's a commandment in stone (and
because copying prior books is much the method of
producing later books --with seeming blindness, at times!).
I can think in general that there might be some knotty solution
such as you seek, in which the tying would not be so surely
secure, BUT any likely tamperer would probably not have
the wit or persistence to doubt it --many people figure that
knots cannot be untied (or they parrot such assertion).
Still, I'm inclined to the worry that real thieves both exist
and know how to use knives (not scissors), and possibly
would take such a seemingly secured pack --the securing
sending a signal of valuables within(!)-- to use strong force
in a safe (for them) other location.
--dl*
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