When you say the brisket was very tender, did you probe it for doneness? The probe will literally go in like a knife through warm butter.
What temp and how much did the pork butts weigh on those cooks? When i cooked them at 225-250ish range an 8lb butt took me 14+ hours.
Have you tried doing hot and fast method on the pork butts? After doing a couple cooks for low and slow I did hot and fast and it procuded great bbq. Hot and Fast method I use, I will run the smoker at 325-350. Once the bark forms and I get the color I want, I pan it up with a cup or so of apple cider vinegar and wrap it tight in foil and back on the smoker. At about 195-200 temperature, I will start doing the bone wiggle test. Once the bone starts to release I take it off the smoker and put it in an oven (that is off) to rest for a minimum 1 hour (normally 2-3 hours rest for me). Then I pull the butt and add in the fat that was collected in the pan and finish with an Eastern Carolina style sauce/dip.
And since I'm still trying to get the hang of briskets, I cook them at 275-300ish. I have had decent results but trying to get it so that the ends pieces don't burn.
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