Fairly theoretical issue I think.
Looking inside the cockpit to keep values at a special point will kill you in the real emergency cause you wonīt see the wires in your approach path or the ditch in the landing area, which will make you topple - unless it is to late.
There have been enough accidents in training - especially when training off airport!
With the height we normally operate in you wonīt have much time anyway (o.k., the old Bell206 sailbird will travel further them most other helicopters)
I think itīs better to get used to achive a steady autorotation shortly after entering, controlling rrpm changes by ear or maximal short glimpse, giving you the time to look out to see, where your safe landing area might be and if you can make it or have to choose another one.
Better have one nearer and weave of some height to make it as going for a far away landing spot.
If you really have to stretch the auto, increase in airspeed with a droop in rrpm can do the job - but you need extra capacity in the cockpit - and on the controls, cause all values change while doing so.....
Just my 2 cents worth.
Greetings Flying Bull