My New Hair Dresser

My New Hair Dresser My new hair dresser has a severe stutter. I have know about stutters my entire life due to public figures that have had them and also one kid in school that I knew that had one in elementary school. I noticed him getting frustrated while explaining things to me due to it taking awhile for him to get a sentence out. I would wait for him to fully finish his sentence before responding and I acted like the stutter wasn't really there. Would it be okay if next time I get my hair done if I tell him that I understand what a stutter is and to know that I am patient and not worry about me questioning what it is? He might be thinking that I am confused by it or wondering if something is wrong with him other than that, which I am absolutely not. And I wonder if It would also be okay if I ask him how he got it? He told me was in an accident and that's why his leg is messed up, so I wonder if that caused it. I'd hate to make him uncomfortable, but I also don't want it to be an elephant in the room for him specifically. What's the right way to ask about it?