Originally Posted by
alan s
Wouldn't worry about compressing the bag with an extra layer on top. Jacket, towel, extra clothes, etc. Even if you lose a small amount of loft, overall you will be warmer. For me, it makes enough of a difference that I'm no longer cold, so all I can say is don't rule it out because someone says it won't help. Try it for yourself.
+1
We often use our insulated jackets (Primaloft) on top of our sleeping bags for added warmth when snow camping, and climbing.
The jackets are filled with the same insulating as the sleeping bag; why would it compress the bag's insulation?
With the new synthetic insulating material, I retired my down bag.