Here is what I think. One of the reasons we are so enamored and or obsessed with this sport is that the whole thing is open to speculation and thatís what we love to do is speculate. Tinker with the idea of it if you will. If we had it all figured out it wouldnít be any fun anymore. I also believe that when the bite is on for what ever reason that they will bite anything you put in front of them. I have lots of flies in colors, and tones that cover the visible spectrum. Its been suggested that fish see in much the same way we do, but perhaps that is just a convenient assumption that allows us the luxury of familiarity. Water is a completely different medium than air, it transmits light, temperature, and pressure in different ways. Maybe color dose matter, but I think itís a small piece of a big puzzle.
I often find my self looking in my fly box at all the colors and then out of habit, perhaps because I have caught more fish with it than anything else selected something purple.