Every backyard cook I see posting their brisket is running their pit at 225 and then wondering why they're fighting a stall for 10 hours. I've been running my WSM at 275 to 300 for the last 3 years and my briskets come out with better bark and way less guesswork. The 225 rule came from old stick burners with thin steel, not modern cookers. Last weekend in Tulsa I did a 14 pound prime packer in 11 hours flat at 285, wrapped in butcher paper at 165, and it sliced like butter. Maybe try bumping your temp next cook and see if your results don't get easier. Anyone else here ditched the low and slow gospel for a hotter fire?