This is a good learning video - once you get past watching it with horror, try watching it from a point-of-view of seeing what they did wrong (you can make a long list).
Then try figuring out how you would go about the rescue.
Then try figuring out how you organise your approach to this drop to prevent this scenario developing.
This is one of the drops in the Triple Drop section of the Travo River in Corsica. It's one of those well-known hazards that's fine if you do it right. We were there a number of years back and had no problems because we didn't mess about. One of the group behind us, however, took a beating like this guy.
The key lesson is this: never paddle with Germans in Topos, especially if they are wearing full-face helmets and elbow pads. Anyone paddling with 1980s gear probably has the skills to match.
Jim.