They are mono, but I was trying to say that with practice, you can process 2 independent audio streams simultaneously irrespective of whether they are mono or stereo. For example, I am able to keep track of 2 people talking at the same time. I obviously can't respond to both but can maintain independent contexts.
I think it was wondered whether you were having the independent streams panned hard to the left and right ears and if that had something to do with hemispheres of the brain and the processing efficiency.
I wonder if piano players find that easier too, compared to lay people.
I do it too, but I "buffer" one person's speech while I process the other's, and vice versa. Do you process both at once?
I wonder if reading techniques (i.e. human TTS) are also a bit like this. You have to "read ahead" and maintain a mental buffer, in order to parse the sentences so that you can put emphasis in the correct places, timing etc. So the eyes and mind are ahead of the speech.