Stewart Cink
I used 10 fingers, like a baseball bat, until I learned to interlock when I was eight. I've held it the same way ever since. I see this all the time at pro-ams: Someone will have to bend it around trees, or hit a high bunker shot. I'll say, "You need to close it down, or open it up," and they simply turn their hands. You should turn the club, then grip it again with your normal grip.