Learning to draw the head after Andrew Loomis

I had my doubts about this. Why should I learn to draw a head using a standard and why try to create a kind of 3D sketch? Every head is different, so why learn standards at all? Why 3D sketch and not simply draw/paint what i see in front of me? Will the 3D look not come automatically if my drawing is accurate?
There is no simple answer but simply a very strong argument for me to move into this more seriously now. I have been looking into many portraiture tutorials online. Those people that start out by constructing the 3 dimensional form of the head on their canvas (instead of just measung distances in the object plane) accomplish portraits that look way better.

To teach myself, I follow the explanations given by Andrew W. Loomis, author of some of the most famous (and beautiful) instructional art books.
Link to "Drawing the head and the Hands" by Andrew Loomis

I believe in the old latin principle: The best way to learn is to teach! If this principle is true, learning from anybody who teaches is second best, at best....

Front view construction of Mr. Standard in words:

Draw a circle (but think of it as a sphere) with center cross. The horizontal is the brow line. Indicate hair line, then nose and chin line. those horizontals are equidistant. Cut out the sides of the sphere, such that the height of the resulting flat surfaces is 2/3 of that of the sphere. Draw the shape of the chin. The top of the ear lies on the brow line, the bottom at the nose line. The eyes line is located in  the middle plane between top of the head and chin. The mouth is located at 1/3 of the nose chin distance.

In front view things look pretty flat, the true advantage of this approach becomes apparent at other viewing angles and perspective comes into play.

Ear located between brow line and nose line, just behind the the center of the flat side plate.