I hate being hot in a sleeping bag, The whole too hot, stick a leg out, too cold thing drives me nuts. in cold weather I also wear a large beenie that pulls down to my nose that keeps my head and neck warm, kuiu marion 210 bottoms, 210 top, hoodie, even 210 gloves to keep my hands warm if I poke them out at night. IMO this is way way better than trying to use a zero degree bag.
Given the choice of having to unzip a bag that's too warm to ventilate vs. attempting to sleep in a 20 degree bag in honest-to-goodness zero degree temps, it's not even close.
