I have read all the posts with interest as I have no experience with extreme cold, much less extreme cold and camping but I find it fascinating. My questions or statements below might be incorrect due to lack of experience or misinformation but they are thoughts that come to mind while reading.
It seems like through all your scenarios, your success or even your survival comes down to a reliable generator. What if the generator dies or runs out of fuel in the middle of the night. And you don't notice for one hour at -40 will you be able to recover and survive?
You mention heated batteries, but the generator has been off for an hour at -40. Will they function?
A heated propane tank with no power at -40 will fail as the propane won't evaporate or won't evaporate rapidly enough to power the furnace. And the batteries will be cold so the furnace fan possibly can't spin fast enough to lift the sail switch.
At -40 does the truck (whether gas or diesel) need an electrically powered block heater in order to even fire up and save your life by getting you back to town?
