Until I started mellowing out in my mid-twenties, my speech was either manic and with words running together or labored with lots of stammering, incomplete sentences, or even forgetting what I was saying in the middle of saying it.
It must be that chattering happily about my interests, or whatever has been on my mind, is what singing is for most stutterers.
Anyway, after several years of working on it and getting on an effective medication, I've normalized.