I learned my helicopter aerodynamics by reading the section in the AP3456.In that venerable document (Thank You, the UK MoD) the section on autorotation has the phrase "apply aft cyclic to restore Rrpm" Drummed into me since I was a baby pilot. Case closed and no big secret ,as far as I have been concerned.
The second thing I learned and have applied all my life while flying twins and singles is "linger not in the curve of the dead man ,lest the earth rise up to smite thee". I know there are good, well-paying helo jobs out there that require a high hover,but, for the rest of us, that would be a good rule to follow.
Finally, an instructor once made the comment that a good autorotation is judged by the entry not by the ending.He went on to explain that you can be over a football (or soccer) field or over an airport,but, if you screw up the entry after an engine failure, you will still end up dead.The other side of that coin is that you can be over a confined area and yet if you do everything right you will survive.Cuts and bruises and broken bones and a badly bent helicopter,but alive. Fair points,don't you think?
Alt3.