Norm,
I remember the episode of Fly Tying The Angler Art where they tied Hans's CDC and Elk. Engerbretson said he knew Hans and had asked him why he called it CDC and Elk when he used deer hair and not Elk hair. Engerbretson said Hans told him, "because it was based on the Elk Hair Caddis, but deer hair worked better for the effect he wanted." Just some more useless information.