You can teach someone very easily and quickly to dry compound clean a carpet. The primary risk of damage is the selection of the wrong brushes for a particular installation.
However, to achieve a consistently high standard requires a dedicated and highly skilled technician. You could even tackle black top successfully, but in reality, it would take too long and cost too much in product to be viable.
IMO, dry compound cleaning is best left for very regular maintenance and as a problem solver.
The machines, however, when used as an agitator, will move your extraction cleaning to whole new level. I wouldn't work without one.
Safe and happy cleaning
The Ken