For a spoon, I fish it almost exactly like drifting, except it doesn't dredge the bottom, but rather just above it maybe tapping at most a couple times. Most of the time, cast slightly upstream and reel up quickly until just a small bit of slack in your line. I reel quickly because sometimes you cast on a fish and they will hit it almost immediately as it flutters downward in the water, but if that doesn't happen, you still want to be ready to lift it out of the rocks. I keep that bit of slack until I tap the bottom, which I want to occur when the terminal is roughly perpendicular to me. Then lift slightly and let it drift, ideally with a tiny bit of slack still in the line that is above the water. The spoon will be wafting very slowly in the water currents this way. When I feel it start to tug in the current, and the current is strong enough, I back-pedal down where I can barely feel it wobble...if I can feel it hit the bottom as it's going, I lift it up, or slow the back-pedal just slightly. If the current is not strong enough to carry the spoon, then just follow the spoon with the rod tip and lower it as it goes downstream. If it is still too slow as it swings and you hit, lift the rod up slightly. Just try to keep it out of the rocks and you should barely feel the lure action. The bit of slack I try to maintain while drifting is for that very slow action I was talking about. Sometimes, it's just not possible (if the current is slower or the depth is shallower) and I have to maintain some tautness, but if the current is slow, a taut line will still not impart very much action anyway.
It is killer...the last 3 years have me at 55% to 70% of my steelhead on spoons.
When you get crafty, you can learn to cast almost directly upstream into pocket water and reel/thread/waft it through the rocks all the way down, then back pedal as it passes you. Tremendous fun!
Also, a spinner just under the top water is unlikely, unless small and dark in summer and the fish is feisty. Get in their zone and you have a better chance.
Oh, and one more thing. When the spoon swings all the way in, let it hang there wiggling in the water to a count of 3, reel a couple feet very slowly, then bag it and zip it back in quickly. Many fish have hit when I reach 2 in that 3 count
ETA: I suppose I should also add that if the line is slightly slack, watch it carefully. If it stops moving with the current, or you see a tug telegraphed in the line, but don't feel anything, pull it and if the rod is loading, without hesitating, finish a complete hookset...you will either have a rock, branch, log or best case, a fish will shake back