I did see that one. It is pretty cool, but more tending than I was hoping for.
With that being said, I think it is a concept I will try with the Tuscan grill (built between the smoker and pizza oven) when we do a whole lamb or suckling pig spit style...
The concept for the smoker is to use a fire brick fire box (insulated) to generate a large thermal mass beneath the food box above.
The fire box is separated by a diffuser made also of fire brick with a gap around the edges for heat and smoke.
Ideally get the box up to temp and let the heat energy do the rest, regulating air flow to control the smoke.