That really depends who their subjects were. A complete beginner will have better luck from doing more volume as their total poundage will still be low (they are weak).
At a higher level you would find it harder and harder to recover from very high volume. Things like Sheiko do work though, but I feel you really need to know how it works to make it work for you.
As I understand, they were written by Sheiko for one of his athletes. So many of us have just been copying straight off the bat some random athlete he trained. He has so many athletes though and it's more his knowledge and how to change the training than simply the %s you do.