Thank you for so detailed informations!But the cases like imitating PWS to catch stutters are similar to mine and I saw many psychogenic PWS are still persistently stuttering for some reasons so yeah it's hard to distinguish psychogenic one from developmental one just by words. But speech interventions like reading articles,practicing self-dialogues and pronounces were all in vain and even deteriorating my stutter during that time.But after I gave up beating stutter,my stutter had faded away and no longer I suffered from [it.So](https://it.So) that's why I place myself in psychogenic PWS.I was a very healthy speaker from birth to 12 and I was complying to the average boy maturity,no earlier or later puberty spurt or something.