I know a lot of people think this, but he reminds me of me on some my bad days with ADHD (and mine is minor). I'd fumble words and keep running on anyway and eventually circle back and correct things. People had a hard time following. It got worse when I was anxious. I also have a horrible memory because of it. I'm lucky to remember what happened last month; forget decades ago. Is it possible he has undiagnosed ADHD?