Make the rub. Place the salt, sugar, paprika, chili powder, pepper, onion and garlic powders, and oregano in a bowl and stir to mix. Place the brisket in a roasting pan and generously sprinkle both sides with rub, about 3 tablespoons per side. The excess rub will keep for several months in a jar. You can cook the brisket right away, but it will be better if you let it cure with the rub for several hours, or even a day ahead.
Make the mop sauce. Combine the beer, cider, cider vinegar, coffee, stock, oil, Worcestershire sauce, hot sauce, and salt in a bowl and whisk to mix.
Set up your grill for indirect grilling. If using a charcoal grill, rake the lit coals into 2 piles at opposite sides of the grill, placing the foil drip pan in the center. If using a 2 burner gas grill, light one side and cook the brisket on the other. If using a three burner gas grill, light the outside or front and rear burners and cook the beef in the center. If using a 4 or 6 burner gas grill, light the outside burners and cook the beef in the center.
To smoke on a gas grill, place wood chips in the smoker box if your grill has one, or wrap in foil, poke holes in the top, place the resulting pouch under the grate over one of the burners. Run the grill on high until you see smoke, then reduce the heat to medium-low (300°F). If using a charcoal grill, preheat to medium-low. Just before putting the brisket on, toss 1/2 cup wood chips on each mound of coals.
Place the brisket on the grate in the center, over the drip pan, away from the heat. If using bacon, drape the slices over the top of the meat. Do this if your brisket is really lean.
Indirect grill the brisket until tender, 5 to 6 hours in all. If using a charcoal grill, add 12 fresh coals and 1/2 cup wood chips to each side every hour for 3 to 4 hours. (You're looking for a dark brown crust.) Generously baste or mop the meat on both sides with the mop sauce once every 45 minutes for the first 3 to 4 hours.
Tightly wrap brisket in foil and continue cooking until very tender 2 to 3 hours more.
Transfer the brisket to a cutting board and let rest for 10 minutes. Thinly slice across the grain, using a sharp carving knife. Transfer the sliced meat to a platter. Spoon any juices from the foil over the meat and serve the sauce on the side.
