Cant relate to knowing others who stutter but definitely relate to all your experiences. My is much more frequent than what yours sounds like, but there are short conversations where I will be fluent. For the life of me, I cannot, under any circumstance say my name, phone no., address etc haha, so don’t worry about it. I’m going to have to say this important things would have to be some kind of subconscious fear and anxiety thing that comes to fruition in times where we know what we need to say. Also probably just the anticipation that you may stutter doesn’t help either. For other conversations and just general talking, let me know if you can relate, but for me it’s almost like I can feel in my throat the word I will get stuck on. Like I can see the words floating in front of me in the sentence and I can feel in my throat and see which ones I’ll get stuck on, not because I’ve stuttered on them in the past, purely because I can feel it.