Thank you, your report is eye-opening, for I have never cooked anything requiring more than 3 hours (other than yogurt - boiled milk, cooled, yogurt added and then left in the oven overnight).
How about safety? grilling/smoking usually requires someone be nearby in case something goes wrong.
For a hot tasty brisket that was cooked 14 hours I go to a BBQ joint. Perhaps the BBQ joint uses a pellet grill (or will soon)!