These are really the basics of database design. I would argue that you should do these until you know when you shouldn't. That is, you should normalize to this

These are really the basics of database design. I would argue that you should do these until you know when you shouldn't. That is, you should normalize to this level until you learn when and why to denormalize some things for performance, if that's ever even needed. I think it means "humble" as in not trying to teach anything complex or revolutionary.