I'm very interested in seeing where this particular post leads, because it's not only a very interesting topic, it also opens the door, if just slightly, on the old "match the hatch" scenario of course!? (but, then too, all the beautiful fish I've caught over the years on a Royal Coachman, sort of goes a long way on at least partially destroying that theory anyway!?)
"Colors of flies" have always intrigued me so I'm also interested to see what others have had luck with, color and color combo, wise/ "which fish, attracts to which color the most", etc.
When fishing for Sea Run Cutthroat, we almost hide our flies, in shame, lest someone else see them and look at us sort of funny", but the colors we use, are the only color combos that seem to work time after time, and on quite large trout!?!
"Chartreuse-body, with a hot pink butt, crystal flash-down wing and canary yellow hackle over that", is just a hint at what we use!?! "Borden's Special", "The Caballero" and the "Spruce Fly" are a few that have wilder than most color combos but work like a charm, for not only Sea Run Cutts, but also in smaller sizes, for West Slope Cutts and the occasional Rainbow as well!?!
I've also had great success using the "Blue Bottle Fly", for, both Rainbows and Cutthroats, in answer to your question of; "Anyone,else, use blue colored flies?"
Thanks, Stevie-B for the post!