I have fished streams with a foot on each bank, and caught surprisingly big brookies.
They're aggressive and will move across a pool to a fly. They're not picky, so you don't have to have the perfect fly. The perfect drift is not always necessary, so they will tolerate a little drag (within reason). In many senses, they are EASY.
But....
they are very spooky. The key is to not get too close, and to stay low. Obviously this can be difficult in thick brush type situations. But I've belly crawled to get in position before.
Note that generally, you can fish from further away with a dry fly. It's tough in cool water, but by mid May they'll take a dry as well as they take a nymph, if not better, as most of their natural foods come from above. You can float that dry over underwater snag hazards without worry, let the current take it behind rocks, and so forth.
How close you can get depends on water depth, whether there's current on the surface, sun angle, and the like. You get a feel for it after a while. But to start, stay as far away as you can, and stay LOW. Often if I have to get closer than I'd like, I'll approach from behind and walk on my knees or even crawl. The smaller the water, the more important this is.
Bow and arrow casts, snap casts, and the like help out a lot too. I actually mastered the bow and arrow by practicing INSIDE. I got good at hitting the bathtub from the hallway, lol.
While everyone's advice is true about using short rods in tight places, when it gets REALLY tight I actually prefer longer rods sometimes. If you get proficient with a bow and arrow cast, generally speaking, you can throw about 3 times the rod length in fly line, plus leader. The difference between 18 ft cast on a 6 ft rod and 24 ft cast on an 8 ft rod can be significant, and the difference between catching a fish or seeing a dart go under the bank.
I prefer to approach from downstream as you can get a little closer, but that's partly because I got good at casting in tight places. If I couldn't cast at all, I might be relegated to approaching from upstream and feeding out line, as duckfoot does. And to be clear, YES, that does happen when the downstream approach is so freakin clogged up with brush and stuff. And some holes are just so nasty I just skip em altogether and move on to easier water.
Ya gotta do what ya gotta do.
Truer words were never spoken. Cover water (no more than 2 or 3 casts to a spot and move on, if you didn't get a hit right away, there's no fish there or else you already spooked it). Don't fret if you screw up, we all do, and the nice thing about these streams is that if you screw up a hole, there's another hole very close. The point is to fish as many holes as you can, and with time, you'll screw up a slightly smaller % of them!
Approach each spot like a mini golfer approaches each hole. i.e. think and decide what's gonna work best. Sometimes you gotta be inventive.
