I have seen a video on choral speech(forward speech) before and yeah it's an interesting research According to my understanding: Defensive mechanism gets activated due to the perceived threats in our mind which results in stutter. So if we priotize forward flow of speech over accurate error free speech we may lead to stutter remission. I think that's what happen when I'm Exhilarated to talk to someone like my friends - I don't perceive threats.