The Bic lighter in the pocket to heat up a key is a smart move!
I never got anything hot with a Bic lighter, other than the hand I was using to shield the wind with. I know that people love them, but not me. A Zippo will work,in the wind.
You can avoid all the fuss with the lighter by planning ahead and using a little Lock-ease. I keep some handy in this kind of weather in case someone else's lock is frozen. One squirt in the keyhole frees it right up. -19f the other night, and no problem getting in the truck to drive home after a 12 hour shift.
