One of the conservative right, Samuel L. Blumenfeld believes that the whole language philosophy causes dyslexia.
Why are so many parents home schooling? Because they've come to the realization that the schools are destroying the brains of American children. It all starts in the first grade where teaching methods are used to deliberately cause dyslexia and reading disability. The method is popularly known as whole language, or the sight method, in which children are required to memorize a sight vocabulary. That is, they are required to memorize English printed words as whole configurations, like Chinese characters. Sounds harmless enough, unless you understand what that kind of memorization results in: a holistic reflex.
What's wrong with a holistic reflex? It becomes an obstacle to learning to read phonetically. An alphabet is a phonetic system in which letters represent language sounds. To become a fluent reader, you must develop a phonetic reflex, not a holistic one. With a phonetic reflex, achieved through phonics drill, the reader can easily see the phonetic structure of the words he is reading and discern the syllabic units that make up the word. But a reader with a holistic reflex cannot see the phonetic structure of the words, because he has the automatic habit of looking at words as whole configurations.
I don't know what research validates these "reflexes". I am not sure they even exist.
On the other hand, the whole language
dogma philosophy in the elementary classroom is indeed a disaster for many children. So he is wrong about teaching "causing" dyxlexia, but correct that whole language leads to reading difficulty.