Thanks Dave, good question. I suppose it's like any decorative backing or a finish that lays on the surface of the wood. It will stretch just enough without breaking. I would think there are others on here that could answer that better than I could. I do think that cherry bark may actually give a bit of protection but I have no proof....it seems relatively tough.
Hey Brian, thanks for the complement. I saw your boy was working on a bow but I lost track and cant remember what his screen name was. Did he get it finished?
Thanks Marc, you are one of the few i have seen that have routinely used something similar to brush nocks. One thing I thought that was interesting when i built this bow was that brush nocks or bridges effectively lower the brace height on a bow, or at least the brace felt by the limbs. Not by much, but a half inch difference in the brace height, on a bow strung all day can add up IMO.