I initially planned to purchase the Marmot Sawtooth 15* treated down-filled bag for $230 at 43 oz. It seemed like a good compromise considering cost vs weight. Now I'm second guessing my decision.
I spent some time this morning reading up on the effects of shivering on the human body. When your body temp starts dropping, the brain tells your muscles to essentially go into a spasm mode. This is its way of maintaining "homeostasis". In other words, keeping your body at the temperature that it needs to be to work right. I am a cold sleeper. If my son has turned the ac down to 70* and I wake up to take a wiz, I will start shivering. I don't like that. Shivering requires energy. 10 minutes of shivering burns as many calories as an hour's worth of exercise.
All of that being said, when I see something like the Teton Sports Trailhead synthetic-filled 20* bag for $55-$65, I wonder if that means I can crawl into that puppy, in my shorts and t-shirt (not accustomed to sleeping in insulated clothing), and expect to maintain a 98.6* atmosphere inside the bag whenever the ambient temperature is 20*? Or is the 20* rating on the bag the temperature at which, if the ambient temperature drops to 19*, I will die? There is a really big difference there, as I see it. Furthermore, if I'm lying there shivering my baguettes off, I may as well continue on with some night hiking, because I am certainly not going to be getting any rest.
So, given the marketing practices of the day, where everyone is willing to feed the consumer a line of poop, would it be safe to say that if you are a cold sleeper, as I am, to head NOBO from Springer in late March or early April, do I actually want to consider a 15* (or maybe even a 0*) sleeping bag? I thank you all ahead of time for your thoughts.