I'm pretty sure this is what he's referring to.
The person in CAR wants to turn left. Instead of waiting for the traffic in both directions to clear, she turns into the mutual middle turn lane after the traffic in one direction clears. She then waits for the traffic moving the other direction to clear at which point you pulls out of the turn lane.
It's also possible he's talking about a boulevard situation with separate turn lanes. Same type of idea except in this case there is basically no way she can guarantee she won't get in the way.