One thing you don't mention in either article are the hazards and etiquette in dealing with a very busy river - any advice for navigating through a run with dozens of anglers, or avoiding anglers who are wading in your path?
1 - Avoid the river entirely during Salmon season or drift more remote sections with less people (i.e. canyons), if possible. That's part of the point of it anyways (to get away from people, right? - but some like to drift for the sake of drifting to access those out of the way spots or stop and fish the other side of the river easier). Never myself had an issue on a busy Sunday during Steelhead season in the upper parts of the Chilliwack (wouldn't drift the Vedder though - too many guys, too close proximity, not as much of a benefit to it, IMHO).
2 - Wear a GoPro on your helmet/hat. I think if people know they're on camera they're less likely to do something.
3 - If you are coming down a run and you observe the seam or area guys are fishing move away to another seam/area of the rapid/river. Lots of times I'll go down the main wave train where they wouldn't be fishing (if possible) or the other side. Float down the river like a log, if possible, where you make your oars out of the water and remain as still as possible. If it's a distinct but smaller pool of the river and the angler is waded out into it and fishing where you can't really avoid his line, I will drift behind them and/or stop the boat and walk the boat around and behind them (and BS with them about fishing, etc. just to be friendly).
4 - Thank Anglers for letting you float through. Many of them are actually fairly respectful and can see the fun you are having and understand why you are doing it. Some have told me they wish they were doing it. The few who get upset thinking you're going to ruin the fishing don't know that the fish react to you like they react to any other piece of debris coming down river. I've caught fish many times shortly after Kayakers and/or rafters have gone through a run.
Floating and fishing rivers is just a logistics solution to finding those out of the way harder to access (in many cases) spots much like driving from spot to spot and hiking in is another logistics solution. I'm not going to get bent out of shape if a guy wants to put all the money towards buying the boat, dealing with the shuttle and logistics to do a drift, some investment in training/safety gear (whether through the school of hard knocks and/or a course of some sort), and put their life potentially on the line to access out of the way water - good on them. It gets guys out fishing, enjoying rivers, helps the economy and can put guys into fish which is the whole point of the sport anyways.