As a commercial guide of 14 years I can tell you that there were many situations where obese customers had signed up for a class IV trip. As a TL I would often readjust boat loads to be sure that the person of concern was paired with a very senior and conservative guide, or I would take that person myself if allowable. As a TL and manager for a large company it often fell on me to be "that guy" that had the talk with the client. Many clients were very understanding and appreciative that we were thinking of their well-being. Others would get very upset. It was never a conversation I looked forward to. There were times that we had guests that I considered to be on the borderline of whether or not we should have that talk, but at least half the time I just readjusted boat loads and took that person myself, ran in the middle of the trip, and stacked senior guides around me. Anyway, the point is to be a commercial guide you have to have a bit of an ego, and there are times you tell yourself you can get this person down the river even if they shouldn't be there. You trust enough in your experience that things will be ok, and without that bit of over-confidence things would be bad when 3 boats flip and there are twenty people in the water. That confidence is what cleans up the mess. This is a tragic loss but I don't know how you can mandate a change in the way outfitters screen guests. They may show up and say I'm not obese, and you look at them and they clearly are. It doesn't always mean that they're at a higher risk than any other guest. I would always screen the waivers of our guests before meeting them, our reservationists specifically ask in advance if there are any health conditions, they even say, "including obesity." Less than 10% of the time people are honest.
Obesity is the greatest health epidemic in the US, everyone says it. Rafting is an adventure sport and marketed as such. People have to be honest with themselves and choose the milder trip. If you haven't exercised in 20 years it's probably a good idea to stick to the beginner section in rafting or the greens on the ski hill. If you put this on the outfitters you will end up unfairly excluding people that are making responsible choices. It's unfortunate that we live in such a litigious society, haven't you noticed that we can do less and less as time goes by?