Maybe I'm wrong, but my experience with different kinds of heating tell me otherwise. Using AC (or any kind of air heater) has terrible efficiency, in the sense

Maybe I'm wrong, but my experience with different kinds of heating tell me otherwise. Using AC (or any kind of air heater) has terrible efficiency, in the sense that when you turn it off, any small leak will drain all the hot air and you are left with a cold room. On the other hand, using radiating heat means the heat is "stored" in thermal mass in the room, so opening doors or windows have little effect.