The kind of "clarity" presented here as good writing works well if you assume that everything that can be thought can be directly expressed in words, without substantial loss. This is clearly not the case. Language is a very poor medium to transmit throughts and feelings. So the "trick" every good writer uses is this: don't describe something directly, but instead try to construct some secondary clues, hints and a general atmosphere that will start a thought process in the reader's mind which leads to the conclusions you want to bring across. This is the poetic approach, it could also simply be called "writing between the lines".
In my experience, this approach is a much more effective transmitter of ideas than trying to describe them directly, also for the simple reason that the reader will subconsiously assume that it is his own idea.
You need beautiful prose, rhythm and images to achieve that, as those open up this additional dimension. The article undertakes considerable (even pedantic) effort to leave that dimension closed.