David, don't mean to hijack your thread but an idea hit me concerning the CV boots...
How about making them out of teflon?
It's abrasion resistant, difficult to tear, has lousy elastisity but flexible (would minimize the expansion problem), chemical resistance better than glass, an even wider temp range than silicone, shape memory similar to a rock...
This one I know you'll love, it's very light.
You would have to clamp it at both ends since it has no elastisity and possibly texture the flange clamp so it can't creep (although the silicone can also do this).
Possibly a solution to a non-existant problem, but food for thought. Boot tears are the #1 culprit in CV failures that I've seen. Another thing I forgot to mention about silicone is it's tear propagation (nick one of those boots right at the axle opening). Other than the higher cost, teflon seems like a great material for the job.
Not to rain on your parade, you guys have done something quite remarkable. I still can't imagine how you guys built those copper bodies, now this.
You know you're making the rest of us mere mortals look bad...
