AI and Signals Not Recognizing Cars/Wagons?

Apparently AI and signals do not recognize cars. A green signal is presented with cars beyond the signal. The Link-0 is properly placed (beyond the switch ribbon) and facing toward the car. Similarly, AI will drive through a car.
I am probably not the first person to see this. I have no idea how you could get an AI train to transit through a yard with occupied tracks. The AI routing code selects a track that has a car on it and this the AI just plows into the3 car. I tried using a waypoint as a via. However. the AI goes to the end of the destination area (that is the wqaypoint marker in this case), reverses out and selectes a track with a care on it and then a collision.
I am probably not the first person to see this. I have no idea how you could get an AI train to transit through a yard with occupied tracks. The AI routing code selects a track that has a car on it and this the AI just plows into the3 car. I tried using a waypoint as a via. However. the AI goes to the end of the destination area (that is the wqaypoint marker in this case), reverses out and selectes a track with a care on it and then a collision.