I have a learning disability. I am not unintelligent. But I have condsiderable trouble doing ordinary things, like spelling, and punctuating. (I also have some trouble unlocking doors and dialing telephones, but never mind.) I deal with people who think I'm retarded.
W's brother, Neil is dyslexic. G.W. may have a milder form of the same disability. Which does not mean he is unintelligent. It means he doesn't speak well.
I don't know what makes him such a mean son of a bitch. I suffered a good deal of abuse because of my disability, and vowed to be compassionate. Bush must have decided if you can't beat 'em, join 'em.