i imagine it might be bit difficult for a 10 yo to stutter voluntarily, esp among kids of the same age group. But I'm sure the therapist knows what they're doing. I've never worked with kids, and only experience I've is my own childhood. For adults it helps immensely because it helps remove the 'fear' of speaking. Most adults don't go around making fun and shaming others (some do, but its their problem, not ours). We're already dealing with stutter, and adding fear to the mix makes it infinitely worse. Stuttering voluntarily among other adults trains our subconscious that stuttering is ok, breathing and taking pauses while speaking is ok, taking time to say what we want to say .. is ok.