Re: Fast Rivers and "Go To" flies and technique
I love to fish fast water, it's where I spend most of my time when trout fishing. I found you are best off to fish a fly that is very impressionistic. You want something that looks a little bit like everything. In the faster water, the fish isn't going to get a good look at your fly, it's only going to get a passing glance. Let the fish figure out what it thinks it might be. The fish only has a split second to make a take or pass decision.
Unless there is a heavy blanket hatch on, I only fish one of two flies. One is a bushy dry and the other is a 2XL bushy bead head nymph. I have enough confidence in my flies, if I'm not catching fish, I don't change flies, I change my presentation. If I've been fishing dead drift, I'll skate the fly on top, or swing it as a damp fly. Swing it fast, swing it slow. Same with the nymph, sometimes dead drift, sometimes actively manipulated. I fish dry and or damp 80% of the time, usually in knee deep or slightly deeper riffles.
Granted I fish a river that has a very diverse fauna. I don't think the fish in my home waters selectively feed very often, more often they are opportunistic.
Give it a shot.