Good day , as far as the readability formulas are concern, they are just tools to measure or predict how comprehensible a "technical text" might be.
With regards to literary pieces such as prose or poems, applying readability formulas could be such a waste why?
Youre the apple of my eye , and you are beautiful to me may mean the same thing, when using the readability formulas, word, sentence and paragraph length are considered therefore making prose and poem somehow an exception due to the meaning they have regardless of how long or short it could be.
Well on your question regarding what standard should be followed, In our case , it depends on who or what sector of society you will apply the formula.
in our system we apply it on college students so grades that are recommended for college students became the standard passing grade.
hope it helps.
regards
ace devera , Philippines
readability advocate
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