greythorn3 said:if your burning 24/7 i think the ticker metal would hold heat longer also.
That is right, it will hold heat longer, but will it be long enough to keep it over 200 towards the top of the chimney by the next time you put a fresh load in? I don't personally think so.
Since most of your accumulation (when burning properly) should happen at the start of a fresh load, you want that chimney to warm up as quickly as possible. If the stove has been sitting under 400 for a few hours before that reload happens, I just don't see any thickness of metal maintaining 200+ degrees above the roof line in that situation.
The only thing I could possibly see thicker steel helping with is burn through protection. However, burn through protection hasn't been a problem with a UL class A chimney that I have heard of, even in extreme cases.
pen