I always thought smaller splits burned quicker. This morning I loaded my Progress with "splinters" of oak. They were 3 year seasoned oak 16" long split mostly to 1"-2". Most would say this was kindling wood. I packed it tight and let her rip - leaving the draft open much more than usual since it's so cold. I figured I'd be reloading again pretty quickly. Keep in mind the draft was open for good heat, so I was not expecting a 12 hour burn. Exactly 5 hours later there were still tons of flames, the firebox was 1/3 full of wood and coals, and the stovetop temp was 450F and throwing tons of heat. I was not in "cat" mode for any of the burn, there were lots of secondary flames the whole time.This was just as good if not better than if I loaded with my "normal" size splits that are 3-4" on end. I'm starting to think smaller splits pack tighter and burn longer. I am getting about the same total burn time as with normal split size, but I am getting higher temperatures for a longer period of time. My guess is that not too many folks have tried running this stove with wood split so thin.