A friend of mine up north went for a swim in a creek with a healthy scud population (and a healthy trout population, too). A dead drift may not always be the best presentation. I might start tying some with a small sliver of foam to get them to float and swing and dive above a heavy split shot...
[youtube]INqrkT_47js#t=147[/youtube]
Unless he's changed his kit, it was shot with a Nikon D7000 in an Ikelite housing.