@I have a theory:

I would agree, in principle and mostly in practice. However, if one knows better, then they must also know that the same "better" can be done. It is hard, yes, and it takes practice, but is achievable. Exposure therapy of sorts helps immensely. And, if/when feeling overwhelmed, simply ask for a recess and postponement of the discussion. I call it "processing time", and it usually takes a few days, or even longer. I call upon it, when I sense it is required (on my and other side, too).

I also try to familiarize the other side with my own (aforementioned) communication style and idiosyncrasies. I'd say we all seek to at least not be misunderstood, if understanding (in sense of the agreement) is not possible... and being frank and upfront about it - helps.