Good thread. Timely too. Streamers Blue Winged Olives and October caddis are happening, right now.
Here's my take on the dry fly....an October variation on the Flat Caddis pattern. This fly has two materials: rooster hackle and bucktail wing. It sits flat and low to the water, somewhat like the real bug. Floats like a champion. And it's easy to see. One good way to fish now is to knot a tippet to the bend of the big Oct Caddis hook, and attach a #20 wet or dry BWO to the tippet. Set the hook for any swirl 24" or so behind the October Caddis. Trying to spot #20 dry flies on cloudy, windy October days is nearly impossible. Even for whipper snappers. But that big flat caddis even I can see. This one is tied on a #16 scud hook. But as you can see from the photo--the fly is bigger than the hook.