Nice Jon! A crisp slap goes a long way to snapping people out of their shock sometimes. Barking loud orders will sometimes get people going too. I'm not criticizing, you saved that dude. He would have slipped out of his crappy, not worn correctly flotation device if you hadn't been there. Anyone can look at a situation after the fact and see ways to do it better but it's not easy actually doing a rescue in real time. Kayaks on our cold lakes are a bad idea too especially for out of shape old guys.