I don't have the Book to hand at the moment, but I'm fairly sure the full quote is to the effect that "children affect their parents, but not their grandparents". So in Poser, Tie01 would affect Knot, but not Neck or Chest (sorry about the homophones). My experience is that this is regardless of shared but unwelded points, although I don't have the item you quoted. I believe that Poser splits a figure mesh into separate meshes internally, one for each body part, even if the original is all one piece; so the weld statements are essential to define what parts are going to stay together when moved. If you use a one-piece mesh, but omit the weld statements from the CR2, it will split when bent just as if it were made from separate pieces.