I have just been studying up on all of the info on the Wednesday panties and trying to wrap my head around that as well. The sheer volume of information that has been amassed over the years by just regular folks hoping for answers is amazing.
Yes. Obviously they can't take the handle knot apart, as it is evidence, but they did call in a knot expert one time to consult with the BPD.
I always remember him because his surname was Van Tassel, lol. Unfortunately, his findings were among those things that haven't been leaked. People who tie knots do distinctive things that can be profiled, evidently.
The knots used have been characterized as everything from "sophisticated" and "complex" to "basic" and "rudimentary," pointing to everyone from Boy Scouts to amateur sailing enthusiasts to just plain boat owners, to mountain climbers, rappellers and campers.
Oh, and there are quite a few people who felt it could have been someone who knew how to do macrame. That always gets everyone into a "70s memories" discussion of hanging plant holders and hippie vests.
I've never gone to any bondage/S&M sites, but other posters have - I don't know the outcome. They never come back and tell us, lol. Guess they're tied up.