phesant tail caddis dry?

I have tied a couple of pheasant tail nymphs, and it seems to me that a
pheasant tail caddis would better look like a dry fly grey caddis than a
caddis with grey dubbing? Anyone ever try this?

Also, per a posters comment I tried a caddis with just brown dubbing and
cdc as the wing. It looked like a caddis but the cdc would not float
it? I bought a cdc caddis from the half dollar fly store and it did not
seem to have hackle, but it looked like it had something else tied in
with the cdc. Anyone know what it is? Maybe a yarn?