I checked this video out per your request.

You are right. It is fascinating and VERY comprehensive. Perhaps TOO comprehensive.

Some of it was beyond me but some things I learned and recognised.

First, Jim's voice is recognised as Top Shelf or first class which we all agree with.

Second Dean Manuel's piano playing is also recognized for excellence.

The thing I liked most was identifying the "vibrato" in Jim's singing. I was unaware of the nomenclature.

Two things that amaze me is the enunciation with Jim's speech, for example hearing the "L" when Jim said "Talk" or "Walk" among other words.

The other thing is the "vibrato" or warbling when Jim held a note. I find in particularly noticeable in the song "Where Do I Go to Throw a Picture Away", which I have been stuck on recently.

All in all, this video is accurate and a learning experience even if not completely comprehended.