I will tell you this for the first time and others for the 300th time. It does not make a difference how fast it reaches the stall point.... (microwave excluded - actually... microwaved pressure cooked its fine)
The best brisket in Texas according to the state legislature is God damn grilled just about, then its moved to slower cooking (250) after about 4 hours and at times it either rests in a pile or is placed in a sausage smoker to rest.
As long as the time spent smoking allows for smoke penetration (which we all know there is a point a brisket will no longer take any more smoke) and there is an adequate slow down after the stall (whether it cooks from its own heat and rests its way down, or you slow it down... you are good.
Your mistake will be what you do whenever your brisket says "I am Done." or I am "Nearly Done." NOT ANY DAMN INTERNAL TEMP saying its done but your brisket saying its done.
Allow me to make an example everyone can relate to: as anyone who has ever had to knock of a chunk of your sweet-assed 17 year old cousin while your wife unknowingly watches the kids, knowing at any time you could be caught, well... like a brisket, each hot cousin you have has a different "done" point when you are probing and poking them. Also like a brisket... when your cousin is "done" you you don't need to spend time cuddling and telling her how good she was... you pull her off the tree stump you leaned her against and throw her her clothes and git!
LOL
BBQchef33; Edited to remove word censor over-rides.