Brisket can be fickle depending on A) the briskets quality & B) the cooking temp. While all briskets are graded just because it may carry a Choice stamp where in the guidelines did the Cow fall Lower down the easier it is to have an "ut oh" I think I waited to long!
Cooking H& F IMO gives a bigger window to not over cook one because you need a longer rest time.
Pork butts I don't use a probe I go by the Bone as it is more right than the probe; the last place on a Butt to give it up is closest to the bone, so if the bone is loose and wiggles easily it's done. Probing you will hit spots that in your mind say "Yeah baby this gonna be Good" only a few hrs later to be disappointed because the meat closest to the bone is still firm.
As for over cooking one they are forgiving but a long carry over on a loose bone butt if not vented will give you pork mush which is good for Tamales, Burritos & Paposas so it aint a total loss.
I never met a Cow that I didn't like with a little Salt & Pepper! Certified PORK-A-HOLIC