It’s a neurological disorder. Scientists don’t even know for sure why people stutter. To claim that you have the 100% cure for all stutterers is asinine to be honest with you. Unless you’re a neurologist on the breaking edge of your field, the claims you’ve made here are BS. Just because you and another person had success with speech therapy that doesn’t mean that everybody will. Saying that people need to just “do critical thinking” when they don’t believe some random guy on the internet who isn’t a doctor when he says stuttering is completely curable is wild.