Staying warm between dives

[DetectorGuy]

I have heard of divers doing this and I have never tried it before. When I asked this knowlegable guy about this, he told me that it is a myth. He said that when your body is cold, neurons near the surface of the skin trigger a signal to the brain. The brain tells the body to send extra blood towards those cold areas. When you pour hot water in your wet suit, the neurons tell the brain to send less blood to the falsely warmed areas and therefore when the warm water turns cold your really really cold. This made sense to me, but I could see how this could take the chill off after a cold dive. I am undecided...