I think if you checked with mills that make commercial carpet they would say something akin to what Bill said. Use it as an interim appearance management method.
Since specialized carpet cleaners are a small part of the cleaning service sector, and a smaller percentage are any better than the average institutional cleaner, the mills have to go with the method most likely to remove carpet damaging soil without having the operator screw the carpet up in the process. Although tip bloom and other agitation related probems are often quoted as a reason to avoid rotary brush or bonnet cleaning I've run into more problems caused by the accumulated gunk left from multiple high-residue, no-rinse cleanings. From my experience working with institutional cleaners I'd say they are more likely to damage a carpet using any method but HWE, so I can understand why a mill isn't going to OK no-rinse as a primary method.
