Feet are interesting. I usually wear one pair of socks, Smartwool hiker socks. Usually I find that my feet stay warm as long as I keep moving. Wind is a problem, because it goes right through the mesh shoes and socks, but we don't have much wind here. As long as I keep my core warm (hence the wool or fleece vest as first layer), it's almost like my "thermostat" opens up and I can feel my feet warm up. I get concerned if I'm out for more than a couple miles and my toes are still cold... Similar to cross-country skiing... those ski boots usually aren't well insulated, and I don't remember being able to wear more than one pair of socks in them. But as long as your body/core stays warm, your extremities will too. Within reason, of course. Sometimes it just gets to be too much and it's time to go inside!