Obviously, that works. I prefer the slightly different method I was taught by the USAOC&S back in 75. It requires a (one) "tool".
The tool is a pin, punch, pencil, rifle bullet, toothpick, twig, etc., essentially anything that can be used to push in the firing pin.
He begins his strip of the frame by removing the safety lock (thumb safety), clearly, this is easy to do on his gun. I have met guns where it was NOT easy, or even possible by hand, until after you remove the main spring housing pin.
SO, the method I use is to use something to push down the firing pin, so it can be removed, then use the firing pin as the pin punch to remove the mainspring housing pin, THEN remove the thumb safety, and continue to strip the piece.
I also note that in the video, he called the frame "stripped" with the grips still on it. I don't count that as fully stripped. The grips are also removed, using the sear spring as the screwdriver.
I don't know of any more modern "improved" gun designs that let you do this. Can you do it with a GLock? a SIG? anything else?
I don't have a Glock, have a SIG, and while field stripping the SIG is a snap, after taking one look at the insides of the frame, well, this old boy "ain't goin' there" save in direst need.
In the century plus of use, to date, no one has come up with a handgun that does all the things the 1911 design does in one blended package. There are many designs that do some things better than the 1911 does, there are many that do things the 1911 doesn't do. Even with decades and decades of being able to study the 1911 design, no one has been able to produce something that is significantly better in ALL ways.
IF that isn't genius of design, explain to me what is, please...