I'm doing brisket as my weekend project and I got a 15-pound one and started it last night before bed. 180 super smoke all night long (8-9 hours). I wrapped it when it hit stall (approx 165) in butcher paper and bumped up the heat to 250 and let it go until it hits 203. My probe went off and I checked it and I was getting 203 towards the middle area, (more around the point) and then I checked the flat and I couldn't even pierce the brisket. How is that even possible? It shouldn't be that "tough". This is a good prime brisket with a great fat cap that was trimmed by myself. My smoker is working perfectly. I'm confused.