It’s been a while, so has anyone come up with anything new they want to pass along. In learning to do braided bodies recently I found that the instructions called for holding the braided material while re-attaching the thread. This obviously calls for a third hand or a prehensile tail. My solution was to put a drop of superglue on the hook shank just before the last weave. Hold the ends of the material for a moment and you can trim the ends and wrap over the end of the weave with the re-attached thread easily.
A simple knot may suffice to keep the weave/braid in place while reattaching the thread, but haven’t woven something in quite sometime. Maybe, pinching the material while holding the tag end of the thread both under tension while starting the thread would work better for material such as “D” or “V” rib. Oh no, just got an idea!!
Somewhere I saw the idea of not removing the thread at all. After the material to be woven is attached - and perhaps a drop of glue is applied, just hand the bobbin over the back of the vise (near the clamp or top of the post). Then when weaving is done, hold the two materials in the left (non-thread hand) and bring the thread to the front. Make a few wraps on the hook like you are staring fresh, and then tie off the woven tags. Proceed with the thorax or legs or whatever. After the fly is finished, then you can cut off the thread that has leapt (under the belly) from the back of the hook to the front. Or leave it, if the fly is small enough and woven with embroidery thread (or large and woven with chenille, which will hide the tying thread).
I solve the problem by weaving with wire.