A pot roast is NOT a brisket cut, but can be cooked in the same manner, slow and long. Right on about the carrots, onions and potatoes. Leave out the celery. Too chewy.
Zero celery. I never saw that in my mothers pot roast. If she was here (alive) I would ask her what cut of meat she put in. This was the age of neighborhood butchers when the mothers had their favorite ones and most were stay at home moms though mine did accounting work off and on
Her pot roast was braised in the oven. So it cooked at higher oven temps than you can get just simmering on the stove top