I don't understand it. For instance, "This means the language should be interpreted as used in everyday writing and speaking." ? What does that mean in relation to literal meaning?
You got it. Same way we talk today with several expressions, same way the biblical reading is a common language like any other one.
Of course, there is a liiiiiiiitle problem.
It happens that lots of those expressions can't be understood properly because the several events that made the generations to be out of the original traditions.
Like to say, that after a world war, the expression "piece of cake" is not longer used because people only use words for survival and the culture has changed a lot. After three thousand years, someone finds a page of a book where such phrase "it's a piece of cake" is written. The new readers will interpret it in many ways until they find more readings and compare and find out the meaning.
Sometimes are words which meaning can't be decipher at all.
However, even with these obstacles, the readings can be interpreted using other manuscripts with Semite languages.
Another problem might be the interpretation of the readings following the traditional pronunciation. This also gives you a different meaning to the texts. Just one vowel sound can change the whole sentence. I did it, and gave me interesting results. Lol.
But, as far as I can see, the writings are telling you straight a narration that can be taken as literal when you understand the meaning of the words as they were understood in that far past, not by the meaning some interpreters given them with today's understanding of those same words.