Ed trying to get an understanding of great BBQ from reading a forum is like trying to understand women by reading a book. You must go forth and sample the Q at many places and then you'll begin to understand good BBQ. Like women, BBQ is a complex thing with many regional differences. Also like women, the quest to understand them may leave you frustrated and broke. BBQ refers to both the food and the equipment, but the gas BBQ you refer to is more correctly called a gas grill. When on your Q quest, ask the pitmaster to see the pits, they are as varied as the products they produce. In central Texas, the meat is usually cooked on a pit (Saltlick, Cooper's, Hard 8, every place in Lockhart to name a few). Other places use old propane tank looking smokers. But the method is fairly common regardless of device - lower temperatures and lots of smoke from the main heat source of wood.