I'm familiar with Bill and I actually like him more than other fluency shapers (maybe because I don't know him much), but my issue isn't necessarily with the implementation but with the ethos of fluency shaping: stuttering is bad; fluency is good; you must control your stutter. Instead of teaching people to suppress a part of them, I believe it's better to teach them to accept themselves and not to let it stop them. Plus fluency shaping doesn't last for the vast majority of stutterers.