The recording yourself helps because the anxiety of the stammer makes me (not everyone) quite tense in certain situations, and as such, makes the blocking worse. So practicing, and recording myself desensitises my brain to those anxious situations, and as a result, this is the beginning of retraining the brain to react differently to it. I mostly do the breathing exercises as an exercise on its own, which in turn helps with mindfulness and also can reduce the anxiety/tension built up by the stammer and anticipation itself. Hope this makes sense.