Yeah, it's interesting, but that's where its usefulness stops. You literally do not want to generate private keys from text anymore because i) if you use pre-packaged tools to do it, they use an algorithm is known by all hackers and they are running programs to brute force private keys with random text ii) if you do this manually with a different algorithm you could forget it, if you also lose your private key.
Don't underestimate the forgetfulness of man. it just struck me again with a few passwords to some services. (I was locked out of LastPass during that time).
Try to guess a private key with brute force it's like impossible if I'll take in account a random text with 500+ characters/special ones/spaces...
Of course is not easy and it's like a waste of time (versus create a private key in the classic manner) since I can use other methods but what I think it's interesting it's the chance to hide a private key inside a text.
About the method to create this wallet, all steps could be easily saved everywhere... I was searching also a way to do everything just from "command line" and not using tools or other stuffs online.
BTW thank you all for you inputs and clarifications, much appreciated