Playing with alternate patterns of breathing like you describe is something I've never tried. Your "broken" patterns sound really interesting, but I'm struggling to understand your #3 pattern. Would you explain again?
Dumb question but was there any wind the day of your swim?
re hyperthermi, that's my deal breaker for OW. I'm a "nonresponder". Today in 18', and after just 400m, my temp was down below 34'. The problem is that I feel fine when this is happening, no shivering on exit, just a sometimes quite subtle loss of co-ordination. Really irritating, espeially today as I found I can now swm comfortably in 6 m/sec winds and that it's really fun!
A psychological disorder is: "Any personal construction which is used repeatedly in spite of consistent invalidation."
~ George Kelly
"The water is your friend.....you don't have to fight with water, just share the same spirit as the water, and it will help you move."
~ Aleksandr Popov