I haven't used a charcoal grill in a long time (used gas grill) so I decided to start using one again and bought just a small Weber Smokey Joe grill since it's just the 2 of us. My question after reading through the manual (a guy reading a manual, crazy) is it says about how to cook different meats and vegetables to use indirect or direct high, medium, or low heat. I know how the indirect and direct part works but how do you know if you have high, medium, or low heat or does it even really matter? Does it have to do with how the vents on top and bottom are positioned?