I use 18" wide and call it good. We could use 20" wide and there would still be grease under the foil. Don't sweat it, it's a smoker.
Exactly... my foil covers the bottom of my #2 completely and I still get grease under it. When I replace the foil I'll sometimes use my putty knife to gather up and dispose of excess grease and droppings throughout my smoker if there's a lot of it. Otherwise, I don't sweat it.
