Falling off a log raft is different than out of a boat-boats, for the most part, have something to grab onto to haul yourself back on board. A log raft has slippery logs-putting your fingers in the gaps is only asking for broken fingers. Poorly planned-I hope that friends tried to talk them out of it, instead of encouraging them to do so. Sometimes, bravado wins out-but nature doesnt care about bravado. Or, about you at all. It just exists.
My buddy wanted to try out a new Coleman inflatable kayak a few weeks ago-days after our epic rainfall here. He wanted to go on a river. It took two days for me to convince him that, one, new equipment needs to be TESTED first; two, the water in April is too cold for casual river running: three, the water levels are WAY too high-especially for novice kayakers (which both of us are); and four, a nice flatwater paddle is more relaxing than running rapids your first time in the water-unless you have experience.
Fortunately, I won out-we did some kayaking on a few lakes. The website said the kayak he bought is rated to class IV-I doubt that though. Mine, which is a semi-rigid inflatable, is only rated to a class III-not that I have done one, nor intend to in it, but I think that the people who rated mine were more qualified (the one I have is simply better built-the one he bought is more like an inflatable canoe, with a skin over the top)and independently rated-by kayakers. I like to think that I saved his life that day, and he owes me a beer