So, what hard won lessons to take away from this?
1. Don't kite in offshore winds without a dedicated chase boat or someone watching you from shore to send one after you if needed. Kiting solo has its problems too and has been the undoing of quite a few riders over the years.
2. Don't assume the wind will stay constant. It can boost to hazardous levels, die, change direction, sometimes multiple times impacting the wind speed and potentially your ability to kite where you need to go. Know about wind shadow what causes it, impacts on kites and how to avoid it.
3. Never kite past a side or onshore wind landing area to an offshore wind landing area, particularly one loaded with rocks There is just too much that can go wrong.
4. Always do proper weather planning and monitoring, more about that in the upper two stickies at http://www.fksa.org/forumdisplay.php?f=29
Resources will vary in quality from place to place. That puts the burden on the kiter and more experienced hands in the area if present about what the weather and wind might do that day.
5. Don't fall victim to "Last Day Syndrome" or any other artificial deadline which causes you to ignore your own good common sense. No session or part of a session is worth the rest of your life. When it is time to go in, do just that promptly well before hazards arrive in whatever form they might.
6. If your kite goes down and is drifting offshore, immediately setup for self-rescue. All kiters should be well practiced in a variety of techniques for packing down and self-rescue, without exception. You can sail pretty close to perpendicular to the wind using the kite as a sail. Trouble is, if the wind is dead offshore that may not get you back to land but see you drifting further offshore as you travel roughly parallel to it. If you put yourself in a situation like this through a serious error in planning/judgement, you may need to tow your kit in using your swimming skills. Wind drag may suggest dropping the pressure in your kite's leading edge. There is some disagreement about ever doing this but if needed you can blow it back up my mouth, partially anyway, it needed buoyed by your impact vest. Carrying reasonable safety gear just makes sense particularly when things don't go to plan.
7. It isn't known if the kiter was still trying to sail back to the island or was attempting to mark his location with an airborne kite. Either way, he was trying to do what little he could at that late time to help himself. This is important although prevention is a lot better and worth focusing on. Without the flying kite, it is possible Cedric might not have seen the kite at all and missed recovering the kiter.
These are just a few considerations, there are still more lessons to be taken from this experience. Kiting can be more complicated that it seems at times. It can be more than simply controlling a kite but knowing the environment you are in and the variables acting on both it and yourself and managing them properly. Failure to take steps to gain this awareness can set kiters up for problems.