Diaphragmatic breathing is using your lower stomach to breathe instead of the shallow breathing we do with our chest. If you take a deep breath, you can feel your stomach expand. As you exhale, you begin speaking and speaking for myself only, I speak with 100% fluency. It may sound a little robotic at first but when you keep practicing, it starts to normalize and I use it in my everyday life. As for hypnotherapy, this was instrumental in my speech therapy because people don't realize how important your subconscious mind is and how rewiring it can have great benefits.