I'll tell you what purple when it's 15 degrees out I just plain freeze my arse off. I carry enough layers in to outfit a small army and the pac boots have been on since November but still the cold seeps in!
I know I shouldn't say this but I have become very fond of "thermocare" heat wraps for the back and am waiting for a clothing line that is made out of handwarmers to be introduced. Not worthy of a sack punch but should be good for a man card point at least.
It's a tough time to bowhunt and for the next couple of weeks the ML will be carried. The ML at least gives you the feeling you can get up and wander a bit on the crunchy snow.
The big question is how long you can sit in a tree stand in really cold temps. I've shivered so bad the treeI'm in is shaking a bit too.