I have to agree on number of dives in a day also. I pretty much dive dry all year long, not becasue I get cold, I find it more comofortable. in the 1000 Islands, where I dive most, in late july and August, the water temp gets above 75 Degrees F, and on 85 Degree plus days, Ill dive in shorts and a Tshirt. Otherise I might use a 1/2 mil dive skin during those months. Other than that, dry all the way, in warmer monts, I wear lighter undergarments, and i layer up as it gets colder. Really just have to try and see what makes you comfortable..