It works to the extent you practice good habits. As with anything else, practice makes permanent. If you practice good breath control and fluent speech, it will help. If you don't, it will just set bad habits even more firmly into place. So focus on paying attention to your breathing, *how* you're speaking, and what the early onset of a stutter feels like. Make sure you practice speaking like you intend to speak in real life, so it isn't just an artificial thing you only do when you read aloud.