This is based on my experience with my Backwoods which operates the same way as a Humphrey smoker. Lump burns hotter than briquettes and is not really need in these types of smokers. Also, unless you pack the lump real tight, there is a lot of air space in the fuel leading to a fast burn. For that reason I use only briquettes in my smoker and find they give a longer burn time than lump. I know some will disagree, but this is my experience.
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