We used to race a smaller boat (Enterprise) in the winter, and most of the fleet found that they liked the yellow sticky-grip builders’ gloves that sell for about £2. I subsequently tried these in my Laser and they were no good because they went soggy, as my hands were always getting wet. But in the Wayfarer they are fine, mainly because I find I can keep my hands dry, and take the glove(s) off for a moment if it’s necessary to reach into the water, to tighten the rudder stock for example.
For total submersion – personally I would work on avoiding that! – you can’t beat neoprene gloves, although they’re difficult to dry unless you turn them inside out, which for some reason seems quite difficult with the ones I’ve tried. Almost completely dry hands, and quite “grippy”, but they do tend to restrict circulation unless you have just the right size. Poor for manual dexterity.
A couple of years ago, sailing the Wayfarer in N Norfolk, I forgot my gloves, and not wanting to risk wetting my walking ones I tried sailing with bare hands. Snow and ice on the ground, but no cold hands! I admit that there were two other people in the boat keeping most of the spray off me, but quite a revelation all the same. (Normally I wouldn’t want to sail in much of a blow without gloves because of the risk of rope burns).
I reckon the secret is to start off warm and keep the rest of your body warm. Try the £2 gloves, (but keep them dry).