I've said many times an overthought brisket is an undercooked brisket. I've been down that road. Technology has probably caused more dry packer brisket flats than any cooking/smoking method. I now use as little tech as possible and get melt-in-your-mouth flats and points. The VAST majority of the packers I smoke are the cheapest Select grade I can find.
I get my smoker stabilized with TBS, load the meat, and check the chamber temp after 4-5 hours. By that time the cold meat heat sink internal temp will have risen enough that a true chamber temp is shown. I adjust my vents to get a temp I want, usually 225°F, and go to sleep. I do not use my meat probes overnight because I'm too tempted to keep checking the meat's progress.
Next morning I'll check the meat temp just to get an idea where I'm at, which is usually somewhere between 165°F and 185°F. I wrap the meat in foil with a little beef broth, insert a meat probe, crank the chamber temp north of 300°F, and start probing the FLAT thru the foil for a little resistance around 200-205°F meat temp.
Into a pan still wrapped and into a 170°F oven. My center oven shelf is actually 155°F. I leave it there for 3-5 hours while I run errands, work, or do anything but think about that meat.
Then it's slice and serve time.
One point to mention here. I don't understand the "let the meat cool before putting it in the oven, cambro, cooler, etc. Heat flows from hot to cold. If you put a 200°F‐205°F hunk of wrapped meat in a 150°F-170°F oven, heat will flow from the hotter meat to the cooler oven until it reaches equilibrium.
Anyway, once I went more hands off, I've only had successes. I love tech, but it isn't the answer to perfection.