What it is
Dual-tracking is running two channels at once in a conversation: your own inner process (what you feel, what you think, what you want to say) and a live read of how your words are landing on the other person.
Most of us can do one at a time. Under pressure, the second channel is usually the first to drop.
How it shows up for me
This is my weakest link in heated moments. I get so busy being right inside my head that I stop watching the face in front of me. When I manage both, the conversation goes completely differently.