Ok, I know about crocheting dreads (already had to do it to one dread where a big loop came loose), but I keep hearing people talking about 'threading' and 'sewing' their dreads. I also remember reading somewhere about some tyep of process that involved actual sewing thread being used in the dread. Where can I find info? Are any of these good ideas? Is it something you do to decorate the dread, or to knot it up, or both?