Which is why I pointed out not just symptoms, but also coping mechanisms. It isn't uncommon for stutters to try to say a word or have a word come to mind and know they can't get it out. That will lead to them searching for a replacement word. This type of self editing is incredibly difficult to do smoothly, especially when you have a camera on you any time you are out in public. It can easily result in the type of fumbling you see from Biden that doesn't come across as stuttering.