JBB writes in yet another Squawkboxtv comment that never showed up on the blog, "There are also two articles by Linda Sokalski and patterns for Swedish two-strand knitting in Threads' Knitting Around the World (Taunton, 1993). One article discusses knitting with colors with a pattern for socks; the second shows the technique in detail with a white-on-white mitten pattern. "
Thanks for that comment JBB. The Threads book is out of print but you may be able to find it on half.com.
The above photo shows the mitten pattern with the decorative crook stitch. There is a special yarn that should be used in twined knitting and Nancy Bush sells it at Wooly West. It is called Mora and is spun S and plyed Z. (I think that is the opposite of the usual way of spinning and plying, right?).
Also, Theresa of Bagatelle in Norway has done a fine online demo with photos of twined knitting HERE.