But I've also discovered that my method only works if the lowest nail is removed unless the bight folds under the crossing between each nail (I'm sure that's confusing) and enough slack is given in order to allow the frame to gain enough downward momentum to pull free the other slip-folds at each thread intersection. It would be impossible to calculate, though, without mass of the frame and maximum tension of the thread. As those two are not provided, I will disregard this approach.
However, if I'm feeling creative tonight, I'll make a video and upload it.