I ˋd rather concentrate on getting down safely and securing things only, when I have really time to spare….
Amen Brother Flying Bull!
I would suggest eyeballing the Nr on the gauge AND looking out is the better method as Helicopter Pilots live and die by Nr.
Enough....you usually live....not enough....you usually die.
Trusting your ears and a warning tone....is not using the best evidence rule as it takes the Nr gauge, your ears, and the absence of the warning tone to meet that requirement.
One Man's Opinion here....having survived some interesting events over the years where Nr status made all the difference in the world as to the outcome.
I have seen some very low numbers....and had I not looked in to confirm what the Nr WAS.....it might have gotten to a very bad situation as we were dropping turns until I lowered the lever.
Even with both engines running and putting out full power....the lack of Nr can become an issue.