I don't switch because of the heat it creates.
Its 1 hand heads up the whole time, no matter what. Even if you are getting smoked on a high TC situation, you keep the one because of what DSchles said, you want those rounds. If that penn is deep ... you are really in advantageous situation so just rip one hand as fast as possible.
When I am with someone else its 2 hands the whole time. You need to try to get more of those high cards, but sometimes the co variance will take you to the moon, take you to the grave, or create a break even situation.