All Prouty is saying here is that if you are banging along at 145kts it is not necessary to dump collective pitch for entry into the auto.
The flare to hold up the nose and maintain altitude will drive the autorotative region, reverse the flow and maintain the RRPM in the "green". When you reach the bottom of the "green" then the collective needs to be on the floor. If this coincides with airspeed at best autorotative spec, then good job.
Like Coyote said nobody is advocating decayed RRPM. That's just silly....
The other issue is a Huey has a lot of blade interia and a robbie has none. Robbies are pretty slow as well so there is not too much airspeed (kinetic energy) that can be traded for potential energy. H500 are pretty fast and can trade airspeed for RRPM.