I have a moderate stutter and it's usually fine but sometimes certain medications make it severe. I would put yes for a disability even if I only ever had to deal with it occasionally. It will protect you from discrimination. I was straight up fired once because my stutter had gotten really bad and my manager would sigh loudly when it happened. I recorded her and when I was fired, I told HR about the recordings and got a settlement. I also checked yes for a disability on the job application. I put a down payment on my house with that money :)