I agree with your objection (against generality), but I think we should allow for the data that at least some stutterers experience at least some measure of succes with a focus on breathing. Stuttering is basically an umbrella term of sorts, both with regards to manifestion and idosyncracies, but also with regards to methods of management. That's what makes it so puzzling to work with, I reckon. So obviously, we shouldn't stop trying things out - but we shouldn't distribute more or less anecdotal evidence either, of course. Overall, it's important that we maintain a scientific approach, because otherwise, we end up having a lot of stutterers wasting a lot of their time testing out stuff that goes nowhere...