Recent situation: very cold water, steady moderate wind. I see another kiter in the water with his kite intact, but the QR apparently activated. He's making no attempt to relaunch. He's wearing a drysuit but is a few hundred metres off shore. Board way behind him out of reach. I kite past him close and he seems to be just floating there, head out of water, but barely moving. I yell at him and he gives a very weak-looking I think thumbs-up; barely turns his head. I carry his board close to him three times, but every time he doesn't seem to make any effort to get it. Now I'm worried that he's hypothermic or hit his head and is only partly conscious. I know he'll eventually drift into shore but it will be another 10-15 minutes before he gets there.
What do you do? I felt pretty useless. Decided to land at the closest piece of beach (a crappy alternative landing spot), secure my kite ASAP, then I was planning on swimming out with my board to attempt a rescue (from half-remembered lifeguarding from my teens; also I was in a drysuit and impact vest so I would have been OK with the swim). But by the time I'd negotiated the landing and secured my kite, he'd drifted almost to shore so in the end I just kept eyes on him and grabbed his kite when it got close enough. He stood up slowly and walked to shore and seemed OK though still weird (wanted me to relaunch his kite even though his board was nowhere to be seen). I suspect mild hypothermia and/or embarrassment. Anyway, I parked his kite on the land and left (his buddy had arrived by this time).
Thing is, if he had been really hypothermic or concussed, he probably would have died during the time I was going in to get rid of my kite and come back out for him.
So what do you do in this situation without becoming part of the problem yourself??