To be fair, this is an article by a UX designer, targeting other UX designers, for the express purpose of getting their (presumably) already usable interfaces noticed, and appreciated.
If you can accomplish this with 7 simple rules then you don't really have to worry about the subjective parts, and you can focus on the usability.
Maybe so, but the fast majority of designers are designing non-usable sites, so we shouldn't be promoting advice of the nature of "How to run a fireworks show at home" [quietly assuming you are an expert in fire safety]
If you can accomplish this with 7 simple rules then you don't really have to worry about the subjective parts, and you can focus on the usability.