Hmm, I am surprised to hear that people had a good experience with one of those dating services since I have heard generally negative things (partly because the companies running them are incentivized to fail so you don't leave their market).
It is sad to hear that there are so many people so unsatisfied, but not too surprising. Then again, I am pretty sure that TLC has just been about freaks for about 20 years and has nothing to do with "learning", anymore.
I have no idea what the appeal of that rope work is, either, or how it is associated with sex. I guess if you are into it, it makes sense, but to me it just looks kind of interesting, at best. Then again, I am pretty vanilla so I probably wouldn't understand it.