Steve R. wrote:

Actually, from what I've read through the years, even the guys out there
with full blown PhD's in rotorcraft aerodynamics don't fully understand this
stuff so us little peons shouldn't be too embarrassed by the confusion we
feel when trying to get a handle on it.

That much is true. Anyway, you're not going to enter VRS in an auto.
No power, no VRS.

And the problem with a vertical autorotation from altitude to the ground
isn't maintaining rotor inertia - you'll have plenty of that.

-Ryan
ATP, CFI (airplanes and helicopters)