I used to use dun or tan posts to match the wing color of the fly I was tying. I now use black, pink, orange, red, reflective pearl, and whatever else I can see better. I catch just as many if not more fish now because, as Scott said, I can see the fly and the take better. I know La Fontaine said the wing is the first part of the fly that a fish sees, but with a much lower riding parachute fly I believe the the body of the fly in or just under the film is what gets them to strike, not a hatch matching wing color.

Of course, I've been wrong before.......

Joe