I'd guess a "Pro BBQ" would be any place they sell the 'Que to the public. What Scott was saying wasn't that the Brisket would be done in 3-4 hours, just that this is how long they smoked it for. Then they'd do the remainder of the low and slow cooking wrapped up in a conventional oven indoors. There would be lots of advantages in cooking them that way for a commercial kitchen. More control of the cooking and ability to hold the finished meat at serving temp for a long time come to mind.
The other (maybe even bigger) advantage of splitting a whole brisket into flat and point is that the fattier point takes a lot more cooking time to render all of the fat out, and by then the flat would be dried out and tough. By splitting them you can take each piece out of the heat when it is optimally done.
A "smoke ring" is caused by smoke, but not by the white, visible part of the smoke. It is created by the invisible nitric oxide and carbon monoxide in the smoke in a reaction with the myoglobin present in the meat. It's generally the same reaction and discoloration that you get by curing meats with sodium nitrite curing salt (Prague Powder), which is what makes Bacon and Ham red and pink.
The other (maybe even bigger) advantage of splitting a whole brisket into flat and point is that the fattier point takes a lot more cooking time to render all of the fat out, and by then the flat would be dried out and tough. By splitting them you can take each piece out of the heat when it is optimally done.
A "smoke ring" is caused by smoke, but not by the white, visible part of the smoke. It is created by the invisible nitric oxide and carbon monoxide in the smoke in a reaction with the myoglobin present in the meat. It's generally the same reaction and discoloration that you get by curing meats with sodium nitrite curing salt (Prague Powder), which is what makes Bacon and Ham red and pink.