I had a chance today to speak to my buddy, and it is clear I was more out of it than I recall. He says, for example, that I was in the water for about 20 minutes, while my recollection is 5 to 10 tops. He also recounted some of our "conversations" in which I attempted to take part; funny now, then not so much.

With this new information, I think it may be critical to simplify things so a dumbed-down brain has a better chance to make the right moves. Maybe forget the nice-in-theory layered clothing and substitute just a heavy, hooded sweat suit and thick socks. Dry, change, get into the bivy, and get core temperature back up with heat packs, hot food, and hot drink.