That's really interesting because I've felt similar. If I encounter someone with a speech impediment (not stuttering), I am very patient and understanding. But when I heard this man stutter, my immediate reaction was shame and embarrassment because I know that's exactly how I sound. I wouldn't really say I felt immediate compassion either. I think it could easily be our self-hatred of our own stutter reflecting outward onto other people with our same speech impediment. I hate my stutter, and hearing someone else stutter is painful because it hits so close to home.