The ID (Ice Dub) Grannom pattern has been in my box for 3 seasons now. It was tied to match the emergent stage of the common Apple Caddis hatch (Brachycentrus Appalachia) in the Northeast. It has proven extremely effective when those fish are slapping all around you, yet taking nothing dry you are tossing at them. I grease the last 6? of tippet when fishing this pattern and keep in it the film as much as possible. Towards the end of my drift I will often tug the fly below the surface, then stop my rod abruptly and let the fly swing those few inches back to the surface.