- The Misuse of Readability Formulas as Writing Guides
"One source of opposition to readability formulas is that they are sometimes misused as writing guides. Because formulas tend to have just two major inputs--word length or difficulty, and sentence length--some authors or editors have taken just these two factors and modified writing. They sometimes end up with a bunch of short choppy sentences and moronic vocabulary and say that they did it because of a readability formula. Formula writing, they sometimes call it. This is a misuse of any readability formula. A readability formula is intended to be used after the passage is written to find out for whom it is suitable. It is not intended as a writer's guide."
(Edward Fry, "Understanding the Readability of Content Area Texts." Content Area Reading and Learning: Instructional Strategies, 2nd ed., edited by Diane Lapp, James Flood, and Nancy Farnan. Lawrence Erlbaum, 2004)
"Don't bother with the readability statistics. . . . The averages of sentences per paragraph, words per sentence, and characters per word have little relevance. The Passive Sentences, Flesch Reading Ease, and Flesch-Kincaid Grade Level are computed statistics that don't accurately assess how easy or hard the document is to read. If you want to know whether a document is hard to understand, ask a colleague to read it."
(Ty Anderson and Guy Hart-Davis, Beginning Microsoft Word 2010. Springer, 2010)