and leave it on for a bit to crisp up the bark. here are some more tips that improve your chances for a good outcome :
1. inject the meat with beef broth. it doesn't augment the flavor, but does ensure that the inside isn't bland. people think this is heresy, but competition pitmasters all do this.
2. make sure you let the meat rest for at least an hour before serving. I don't wrap it tight when I do this. I just plop the brisket in a turkey roasting pan and cover the top with tinfoil.
3. overdone is better than under-done. Brisket might get a little crumbly when overdone, but it is tough when under-done.