I never had straps or line fail, but once a toggle broke in two, and down I came. I selected a piece of wood that looked like it was thick enough, and the theory is that the whoopie holds to the strap, not the toggle. But the weight of the subject (myself of course) was too much for this wooden toggle. I could not for a minute figure out what had happened there in the dark, inside my HH expedition. Now I use a metal toggle.
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