That's very interesting. I've tried learning speed reading so many times but I have to REALLY concentrate on suppressing my inner monologue and eventually just gave up because my inner monologue always won. Generally I can't read faster than the speed in which I speak unless I concentrate on shutting off my inner monologue. Then again, I'm also constantly talking to myself to the point where it often becomes a dialogue rather than a monologue. I never knew it was possible to NOT have an inner monologue or the compulsion of driving one varied from individual to individual.