BrownTrout01 wrote on Aug 15^th, 2009 at 5:52pm:

Diane experienced a gasp reflex and difficulty breathing in cold water with a full wetsuit, rash guard and splash jacket, but head and face exposed.

I think this is a reaction that's often overlooked when discussing survival in cold water or even sudden unexpected dunking in warm water.
You always hear about the "good" swimmer who takes a dunk, and never come up? It's not always in cold water, where one expects the sudden shock and cold.
 I remember being at a pool party and coming up behind a friend of mine who was a Navy trained diver and recreational scuba diver.
I dunked him suddenly underwater, and he got a mouth/nose full of water, and just flipped out! Once he caught himself, he proceeded to let me have it too the point we almost came to blows :o
I apologized and left him alone. Later he came up with a peace offering beer, and apologized for over-reacting. He told me that even with his training, the dunk was so un-expected, he panicked for a moment, and what he was REALLY mad at, was himself for temporarily panicking.
I think that's a big plus in wearing your PFD, it gives you better odds of NOT getting that mouth/nose full of water, and having too deal with the gag/panic reflex.
 WE all like too think we won't panic when the chips are down, but in reality, until it happens NONE of us know for sure what we/others will do?
 It's good too discuss subjects like this, awareness is the key to survival.