Cold water swimming

Toying with the idea of joining a channel relay team, I have been experimenting with sub 16 degree water for swimming.  To that end last saturday I managed to immerse myself in the Petersfield Open Air Pool.  Gently gently down the steps!
I spent the summer swimming once or twice a week in the 67 metre Hillsea Lido at 17/18 degrees, but 14 degrees was a completely dfferent experience.
Despite taking a minute or two to try and acclimatise, I found it difficult to breathe for the frst 25 metres.  My brain was sending conflicting messages: "What are you doing in here?"  "Get out!" kind of stuff.
Then, surprisingly, things settled down a bit, my face stopped hurting and I started to swim quite well despite contantly being aware of the cold temperature around me.  My aim was 400m but I decided to stay in for an extra 100m which was a moment of "summit fever" I think - the last 50m became a bit of a challenge as the cold started to chill my core.
It was certainly an invigorating experience but don't think I'm ready to join Penny Wilkin on her channel relay this year.  Going back for more on Boxing Day though. (Why?)
The big plus side is what a fabulous convivial vibe around the pool they have created there.  Highly recommended.