Definitely rocks and boulders are good spots. The way Tyson describes this run though it sounds like to me there was just a slight depression in an otherwise ordinary looking run. Polarized glasses definitely help in spotting subtle decreases in depth. I find that rainbows often hold in much shallower water than many realize and when they do they often sit in slight dips that are barely noticeable without close inspection.
Tyson is an unbelievable fly fisherman and I've never used 'coiled' sighters and have only novice abilities, but drifting nymphs/egg patterns over this kind of water will work no matter what technique you use (indicator, czech nymph). It sounds like you're fishing the right water, maybe just not hitting a system with a lot of trout. With coastal systems, the biggest trick is to go where the food is (ie creek mouths, behind spawning salmon, insect hatches when available) because the systems don't have high enough nutrient levels to feed fish everywhere in high densities.
If you message me you're location, I would gladly point you in the right direction if it's a system I've spent time on.