There is a lot of talk about not "over" thinking it, when you cook a brisket. Even that is too involved. The best thing to do is, once you understand the properties of your cooker, meaning you can maintain a desired temperature, is to put it on and WALK AWAY.
Go mow the lawn, paint the house, swap out the transmission on your car, paint a masterpiece, solve Fermat's Last theorem. Just do something to distract yourself. Come back in a few hours and poke it with something sharp like an ice pick or a temp probe. If it takes effort, go distract yourself for another couple hours, come back and poke again. Is it a little softer this time? If yes, check again in an hour, softer still but not quite? Start checking it every 45 minutes or so until you reach that rich buttery stage that is doneness.
Traeger lil Tex, 2 Weber 22.5", UDS
They call me "Dave"
Original Noobian Warlord
Loser of Known Space