Posse pitmaster Marshall Cooper is a man of conviction, especially when it comes to smoked meat. After mulling our recent Roots of Dallas BBQ Tour for several days, he was still stunned by the lack of smoke taste we found on the barbecue at the original Sonny Bryan's, Odom's, Dickey's and Peggy Sue's. Why don't some of the most popular Dallas BBQ joints, some with real wood pits, put more smoke flavor on their meat? Is it because of the cost of wood? Do customers really prefer smokeless BBQ? Or, don't they know the difference? "I would like to know…