That was a distinction I tried to make. I do believe color matters--a lot--in the wet fly context. But less so in the dry fly context. I used to fish (and guide) the Paradise Valley spring creeks a lot. In July and August, in the late afternoon when the PMD hatch fades out, and before the evening sulfurs get going, most fishermen use ants beatles and tiny hoppers. If the fishing is tough (it always is in the late afernoon) they try to compensate by fishing smaller and smaller flies.
I do the opposite. I have caught more big fish in the spring creeks than I could ever count, fishing gargantuan hoppers along the weed bed lines. Yellow gray or orange. Those are the foam colors I have. I can't honestly say I've noticed one color works better than another.
During the PMD hatch, size is critical. But not so much pattern. Like many spring creek guides, if a fish refuses my Sparkle Dun more than once, I immediately switch to another PMD pattern. Same size but different profile. Same color too, more or less. But I'm convinced color is far less important than size. What they actually see, I think, is a dimple in the surface tension--and a not sharply-focused shape outline. And that's about it. Under the surface is a different story.
I know Byron doesn't buy the "change pattern if they refuse" idea. But he's more of an enthusiastic believer, while I'm more of a skeptical experimentalist. It is important to remember (at least for mayfly hatches) that the naturals are not at all the same. Cripples, emergers and half hatched, half drowned and drowned mayflies litter the surface of the water. And the dimpling fish take them all.
RE> Bing Lempke (note to Byron)...............the carpenters are hanging doors today. Installing baseboards. Final floor coat Tuesday. Then I can start to unpack. My CDROMs and DVDs are still all out in the garage. God only knows which box they're in.