Just tossing out some ideas. First off the BP, I love the stuff and have done briskets with nothing more than a light coat of EVOO and a heavy coat of BP and love the flavor, just like the black pepper bacon. Even goes very nicely on a Prime Rib.
I might be going out on a limb here, but maybe the paprika could be the culprit. Maybe it was too much and cause the BP and Salt to cake up too much and witht the temp, burned up. I've used paprika on briskets, but really only just for some added color, nowhere near enough for it to add any flavor whatsoever.
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