1. Trout, even those bright chrome fresh into the Tongariro river fish from Lake Taupo, WILL move up in the water column to smash a fly as long as its fished correctly. At the start of the Autumn/Winter season, I was heaving up to 12' of T-14 with weighted flies to 'get down' to the fish. Through a process of losing a shitwhack of flies, not being able to swing tail outs properly and watching and listening to better anglers than I, I came around to using T-10 and T-8 tips. I snagged less and caught more fish because I was ... wait for it... fishing more! Some fish were definitely hitting the fly in less than 2 feet of water. Go figure. All those grandad aged books that said "to catch Taupo fish you have to be on the bottom..." well, they're wrong. (Not 100% wrong, but nowhere near 100% right either).
2. Small flies on the whole out fish larger flies. The key is to get a balance of size and weight in the fly. At the start of the season I was swinging 4" steelhead flies. By the end I was swinging 2" flies with tungsten beads or cones for weight and regularly pulling multiple fish from pools. For context if I was able to get a hit or 2 from a single pool at the start of this journey I was overjoyed. That's not to say I wouldn't be now, its just an observation that by constantly honing in on your gear and making observations (don't be afraid to ask!) you can get much stronger results. The largest fish I took in Argentina ate the smallest fly I fished all week, a #14 curved hook rubber legged nymphy thing fished actively. That possibly was a hint :)
3. Might is not right. Underhand casting requires precision in setting the anchor and timing. Watch videos and practice!
4. Fish out your swing right-to-the-end. It may take a big hit when you start stripping back metres of running line in preparation for the next cast to drive this one home - fish will follow your fly to the end of the swing and pounce - and this can be right at the edge of the river in stuff all water. If you're not fishing the whole swing including some enticing small strips as your line is completely straight below you, then you're never going to know how many fish spooked off or didn't eat your fly as it was dragged away.
5. This isn't a rule so much as an observation... sad, spawned-out kelts and slabs on the whole will not chase a swung fly as vigorously as a healthy or fresh fish. I caught very few slabs compared to comrades who dead drifted nymphs and eggs. Yes I caught spawned fish but nothing like in the spawned:fresh ratio that nymphers did. Mind you I caught a hell of a lot less fish. Leading to...
6. The tug IS the drug. A jarring reel screaming hit on a swung fly is worth 100 fluffy indicator dips. You wont believe me until you find out for yourself.
7. Do different things. Last year when I knew a lot less than the very little I know now and couldn't cast worth a damn I was hitting fish with the worst possible casts that landed slack and got several metres of free drift as I tried to get the whole thing under control - fish will plain and simple hit a dead drifted swung fly. Its not a tooth clattering hit but when it all comes up tight.. well FISH ON!!!
8. Use heavy as leader. One day on the Big T I ran out of 10 & 12lb. The fish ate flies looped on with 20lb no problem at all. Ok so these are passive aggressive spawning fish biting at the fly for god only knows what reason so this probably wont translate to fishing wee wets or small streamers in your local.If you could get mono/fluro that thick through the eye of your hook. At one point in my career I used to use 6lb in the Big T on my nymphing rigs. I got spanked a lot, quite needlessly.
9. Match your heads as well as tips to the water in hand. 40 cumecs flow in the Big T is very different from 25. I found the Airflo F.I.S.T concept excellent in heavy flow but in lighter its just less effective than a full floater. This of course should seem obvious but I for one fall into the trap now and again of 'it worked last time, so it should damn well work this time...". That my friends, doesn't hold for fishing and we all know it!!!
10. Double hand fishing is stupidly addictive.Much to the detriment of my other fly fishing, I've hardly lifted a single hander this year. This will backfire for me of course when I go out for a kingi or snap soon and can't get my shit together.