Right, I've explained my opinion of speed reading techniques by describing my experience of having tried them. This is the actual, factual experience I've had

Right, I've explained my opinion of speed reading techniques by describing my experience of having tried them. This is the actual, factual experience I've had attempting to use speed reading - on what basis can you say that this is "absolutely not true"? Perhaps you're trying to make an implicit point regarding subjectivity vs. objectivity, but if this is the case, I'd point out that (a) the effectiveness of speed reading is an inherently subjective question, and (b) you responded to my anecdote with only your own anecdote, despite explicitly making an absolute claim.