Their guidance might sound clear, but in fact "Venus" is not the kind of repeated word they are talking about, because there's no unambiguous substitute for it.

If you're referring to Venus, then please ignore that advice and say "Venus" every time, don't annoy your readers by calling it the second planet, Aphrodite, the planet of love, the evening star, and etc etc ...

That is an example of the many severe issues with the advice in this article.