I have awful circulation in my hands. There for i always always wear nice warm mitts. When spring skiing ill break out the park gloves.
As for skiing without gloves, personally i would never ever do it because my hands would be frozen in a matter of minutes.
Funny thing though, a couple years ago at orage's pro's and powder tour, it was around -20 C so pretty cold yet when i was riding up the lift with TJ i noticed he was wearing no gloves. I asked him why and and he said his hands never really get cold.