WOW!! After reading the mail we received about the cold nights I immediately checked my sleeping bag.
Ironically, my son in law told me that the fewer clothes you wear in the bag, the warmer you will be. It seems that the bag supports the heat that your body emits. If you are over dressed the heat just doesn't develop. He says to start out being warm, get into the bag and get naked!!!
I can confirm that during the winter, I sleep under a down duvet and wear next to nothing. (uh oh, the secret's out). But then again, I'm starting at a room temp of about 20*C, not 5.
I think perhaps drinking ginger tea before retiring may help. Food for thought.
Michal, about the well kept secrets...'When in Rome...." I guess we have to play by their rules. I am confident that our crew is very strong and you are definitely the Super Glue that keeps us together. Kudos.