I thought I responded to this?
You, trowpa, those funny leadened masses you drag across the bottom in a dead drift? Imagine those same things, but without the 12 pounds of lead wire and tungsten beads, and fished the same way, you know like sort of upish and across then dead drifted down?
You fish them like that. At the end, when you pull the whole thing otu of the water to re-do it? Resist the urge. Let it sort of get pulled down and across. Mend, if neccessary, to keep it slowish. Wait for tugs.
When its done, and its hanging downstream, wait. I know, its hard, because you're like, "the drag, it is ruining my drift, and the fishes, they know." But thing is, dude, they don't know, coz they're fish, and because you've replaced 12 pounds of lead and dubbing with something soft with wiggly bits of feather that come to life as the water goes by, the fish they think, "this is alive, and swimming and tasty food!" So they watch it, and strike it.
And if that hang, if it still don't produce, you give it a twitch. One, two, three. No? Fine, Lift it out and recast it.