Almost all my caddis fishing seems to be with dries. I know exotic caddis pupa, divers, emergers and bubble grabbers exist out there because Gary Lafontaine says they do. Once on a forgotten PA river I found some dead October caddis in the water. Big and brown they were, but also dead. On another expedition Bill, Bob Jacklin and I found very large zebra caddis on streamside vegetation in Montana. Alive but inactive, and the fish didn't seem to care for them.
I've never come across a caddis hatch that didn't result in anything other than a size 18 dark. Come to think of it I've never even seen a real an elk hair colored caddis. Think about the hatches you've encountered. Were your experiences similar?
Mark Johnson, a guide for Bob Jacklin in West Yellowstone once told me he thought the most productive flies were the simplest. His rule was, they should be tied with three materials, and one of them should be the thread.
So here's my shot at fame. A simple caddis I've fished with good success.
Hook: Your favorite dry.
Wrap the thread to the bend and return one eyelet length back from the front. You have just formed the body. Stack a small clump of deer hair. Tie it in tip first leaving about a hook gap of hair extending out over the eye of the hook. Equally split the tips and pull them out perpendicular to the hook shank. Figure eight the clumps forming the tips into outrigger like legs. Dam up in front of the legs and whip finish. Pull back the butts and angle cut to the length suiting the size fly.
QC (Quick Caddis)
Fish this fly as you would your normal caddis dry. Of course twitching it now and again during the float can't hurt. At the end of the drift let it swing cross current directly to below you. You may be pleasantly surprised how many fish take it on the swing. I believe due to the flies waking nature.