Interesting concept. I always thought that having the parts that wear out be easily replaceable would be a good idea, but had no idea how to impliment it. One of these days I might "borrow" your idea.

I have yet to actually take up knitting, but my wife(an art teacher) gave me a copy of "The Complete Idiot's Guide to Kitting and Crocheting" that was being discarded by the school, along with yarn and tools, some of which she assures me have a purpose but I have yet to figure out what that purpose is. I haven't done anything with it yet...maybe next winter.