#1 kayak rule for me. Carry synthetic spare clothing. Fleece bottoms and tops, spare socks, black trash bag x2, in a water proof bag. If I dunk, I head to the nearest bank, not camp. I get out of those wet clothes and into dry. Here's my thought, what if you dunked again due to the injuries or stress of dunk #1 that made you stiff and unbalanced.... dunk #2 as you said would be much harder to recover from if you hadn't "recovered" from #1.
The black trash bag, worn as a undershirt after getting cold, traps body heat and vapor losses, you warm much quicker and even more so with exercise such as paddling.
Thanks for posting, good reminder for us all. Prepare for the worse.