I think it is related to the discomfort of someone talking over you. I experience the same feeling of not being able to finish my thoughts even when it’s someone else who isn’t repeating my words over me. If someone starts talking over me I find it very hard to continue to speak. I have been trying to train myself to be more assertive and to continue speaking through the discomfort.

I think maybe the guy who is unaffected is just very good at talking over other people without missing a beat.