No baffle, no indirect. The point of the design is for the fat and juices from the meat to drip onto the coals, and sizzle, and add flavor back to the cook. This design comes as close as any to replicating the taste of the old open pits.
There must be a couple of feet between the fire and the lowest cooking grate.
Incidentially, the early designs for this cooker had no bottom, you made your fire directly on the ground, and placed the barrel over it after it was going. You lifted the barrel off to tend the fire. simple.