I don't know the physics, but it seems logical that a thicker wall would insulate better. Do you want a handkerchief or a thick pot holder to take a pan out of the oven? However, I am intrigued that some thinner walled pipes have to be smoked by handling the shank rather than the bowl because of heat, whereas other pipes with similarly thin-walled bowls never get too hot to handle by the bowl. That must be the quality of the briar. I have a Kaywoodie with a thin wall bowl that never gets too hot to handle and other brands as well.