What concepts from the book haven't stood the test of time?
If I recall correctly, the book was fairly general in its prescriptions.
I'd expect laws of simplicity to be simpler.
The quality of the simple is not reached by simply pursueing simplicity for the sake of simplicity. That will take you instead to the realm of the simpleton.
Ahah, true. I found this book in a bibliotech in Valencia. It is true that it forces you to think a little bit, it is not that simple.