It's not too tough to figure out where things went wrong on google earth. Those two turns would take some pulling to get around. I'm no river expert, but I do own a pro pioneer (the Soar 16's fatter twin) and did sleep at a holiday inn last night. I've also paddled on a 14' otter bailer with a frame, and a 13' bucket boat with frame. I know enough to say that:
1. Oar saddles (such as those on a S16 or PP) don't allow you to pull nearly as hard as a frame (but saddles are way better than paddles - I have plenty of experience in the PP running heavily loaded and alone on small-ish busy rocky fast water with a paddle, and typical result is several close calls with breaking the paddle...).
2. The SOAR boats are remarkably stable, but infinitely less so than a round boat of similar or larger size. Big haystacks aren't much fun in a PP, having been on some during some upper Chitina misadventures...Stability gets better with a load, which gets the floor fully submerged and puts waterline up the side tubes for a wider footprint.
3. Weak people with no experience have no business running busy, fast water, particularly in a raft with no frame. If you aren't a good water reader, you better be able to pull hard to find the late line through and orient the boat and get yourself out of trouble. Problem is, only experience on the oars allows you to both read water and skillfully pull hard. The two big turns mentioned in the story would be trouble for a poorly-manned round boat, let alone a PP or S16.
4. There's no good way to build experience besides running a raft. I'd pulled on lots of oars in a rowboat, but my first significant time on a river had me in a PP on the upper Chitina. Not optimal, and not the way to do things in hindsight. Would not have been fun if I was brand new to running oars.
Absolutely agree with every point you make!
The only thing I think you left out, which is huge IME&O, is the heavy rain and running while the river was still quite high.
