I'll never forget my sister looking at a toothless ole redneck with a beer gut at the checkout line and excitedly asking "When is your baby coming?!" My momma was pregnant with our youngest sister at the time, so we had lots of talks about the new baby.
Only when I hunt in chaps with no pants on my butt gets cold. Otherwise I always thought this was a non-issue. You are wearing a base layer under your outer layer or whatever is the appropriate clothes for the day. If your butt gets cold, your legs will be too having the same exposure to the ambient temps, so yeah this is dumb IMO. Unless you hunt in a$$less chaps. Then this is really important!
By definition, all chaps are a$$less. Otherwise they'd just be pants.
I was hunting in some single digits in the Mantis and thought I was having no issues, then I remembered I had an SBW, put that on and WHAT A DIFFERENCE. Like you mentioned, compressing insulating layers will cause you to get cold in that area (see cold butt syndrome on any hammock forum). That SBW is the bees knees.
Bee's Knees would still be cold, more like the cat's pajamas. Why are we talking like our grandfathers?
See my post #25 above.
