I've done it. Double diamonds with Gudebrod A metallic thread. Looked really cool, but took a few coats of epoxy to get it smooth like the rest of the shaft, and that added a bit of weight to the rear. Also took me entirely too long to do for a dozen. I did one and gave up on it. My shaft was a parallel carbon - no taper. Worked just fine. Most of my rod-wrapping experience with butt wraps is on saltwater rods, so I was used to working with a fairly parallel portion of material.
All the best,
Glenn