So what's the reason in your opinion. Imo when u are 100% fluent with yourself and u get to talk to someone else u have preogrammed yourself to stutter. Im not saying that breathing, tempo etc. arent important but i would say that 80% of the stutter is not about mouth but about your mind and your beliefs. If u believe that u will stutter on Name Eric u will stutter most likely and it doesnt matter that u breath into your stomach or something else.