WOW, WOW, WOW 
You can simply disregard all my above comments in this whole thread as...
Something
BIG has changed in MC since I started this thread.
As we were discussing using the standard Windows Hibernate to shut down, I decided to add the Hibernate command to Win 10's Start menu Power button (as it does not exist after a clean install.) So I went to the Power options & added it.
I fully expected it to show the maddening double popups upon Hibernating Windows BUT... NO darn POPUPS
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What a surprise

. I did not see that coming at all
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So, I tried the other Windows shutdown commands... Shutdown & Restart; guess what, still no darn popups either.
Just before executing each command I made very sure a TV Recording was taking place. After re-booting back up I looked at MC's TV Recordings and in EVERY case the recording had been saved & was currently being recorded. In other words, ALL WAS EXACTLY WHAT I WANTED
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EVERYTHING was working smoothly. TV Recording are now being automatically stopped & saved upon Windows Shutdown, Hibernate or Restart... ABSOLUTELY PERFECT

I also thought "could it be the shortcuts I use to Shutdown, Hibernate & Restart Windows be the real culprit in this long scenario of events?" Such as... "C:\Windows\System32\shutdown.exe /s /hybrid /f /t 00".
So, I removed the /f option from all of them & guess what? They too ran exactly like Win 10's Start Power button commands... NO POPUPS, plus MC was cleanly stopping TV Recording & restarting the recording as soon as MC reloaded after a boot up, Restart or Hybrid Hibernate. In other words, MC was doing it's thing exactly like I need it to do.
I don't know what has changed in MC since starting this thread. At the time I was using 21.0.11, am currently using 21.0.17. I will very carefully review all the MC version updates to try to figure exactly what the improvement is & when it came about.
I'm a real HAPPY CAMPER now.
MC TV may just (eventually after a few more improvements) make my top 10 list of all time favorite programs (MC Audio is already there).
Stay tuned folks.
Cheers.