When you say twist, i assume you mean Reverse twist, or make 2 ply cordage. I assumed this was only for making primitive cordage from small fibers like sinew or other plant fibers that wont hold together using a SIMPLE TWIST(twist your fibers in one direction). But using long strands of linen with a simple twist could work. TTBB mentions that a simple bowstring can be made by simple twisting long fibers such as linen or flax together.The problem with that though is securing the ends so they dont untwist and it is weaker around the knots. I think. Someone correct me if im wrong. I havent read the string section in a long time.
