I've noticed my stuttering has seasons/cycles of worse times, which seem to be tied to stress or anxiety over important calls or meetings. My stuttering has certainly been frustrating and frankly limiting as a founder, since my latest company (https://elasticbyte.net) requires more person-to-person interactions (talking to clients and closing deals).
The singing technique (mysteriously don't stutter when singing), while it is effective, does not work in a business setting. Darn!