Not smarter. Possibly more experienced. I was a never-a-fluent-sentence stutterer. Eyes-shut, run-out-of-breath blocks. Wasn't until my mid-to-late 20's that I got fluent. That was a lifetime ago. Fluency is achievable for many. But not so long as they "*know"* otherwise. You have to be open to the idea that you might be mistaken about your own stutter. That what you know is colored by bias. Which is perfectly natural. There is a lot of traumatic experiences one has with their stuttering. Best wishes!