This.I think every brisket I've done has been at least 14hrs. Usually start in the evening at set pit for 210 or so. In the morning it's usually close to the stall and I'll go up to 225. I inject usually with coke/apple juice and spices. wrap at the stall and cook to at least 195. I put water pan in and the only time I ever open the lid is to wrap. Did a 19lb brisket last month that took almost 26 hrs
"Slow and Low" is the way to go. Its a PITA, but worth it in the end.