How is it insulting ?? This is a popular theory, im saying stutter is a wrong pattern of speech that people who stutters can’t get rid of, it becomes a habit in certain way you speak that causes stutter, most people who stutters does not have a different biology in anyway than a person who does not stutter, so the theory is people accidentally stumbles into stuttering words and their psychology reinforces this kind of habit of speaking causing the stutter, so before you could comprehend properly how does this becomes insulting in anyway? Of course when you stutter you feel this is definitely hard to get rid of and does not feel like you can help much, but most stutterers does not stutter when they are relaxed and not thinking about their stutter, and their breathing pattern and ways of pronouncing is completely different than when they stutter