I understand where you're coming from. My stutter is moderate, and goes almost completely unnoticed with word substitution. But if there's a closed question with no alternate answer, blocks become very visible. The fact that it's not an immediately n-n-n-noticeable s-s-s-stammer makes blocks worse. People don't have any idea it exists until I completely stop making any sound at all. I don't know if I'd actually prefer having a repetition stammer that's immediately obvious. It comes down to getting it out of the way vs waiting for it to attack.