I imagine it’s a fantastic skill, but I also believe I’m not alone in foreseeing such a massive grind to get there from scratch that I write myself off in advance, not having the persistence and intrinsic motivation as an adult—considering even as a child I failed at it (it worked with music but not visual art; I blame the differences in how those were taught to me).
On the other hand, presuming I had some basic ability going (which is what the copy method appears to promise), having proven to myself I can draw at all, I can see myself advancing to this skill eventually.
It is so powerful! You can draw comic strips to serious fine art almost effortlessly after understanding the construction of the form.
I just think that it is the only way to learn how to draw because it is a superset of everything else.