If you watch the Tesla AI day presentation they explain the separation of duties that kind of explains what's happening. The actual routing comes from somethin

If you watch the Tesla AI day presentation they explain the separation of duties that kind of explains what's happening. The actual routing comes from something like Google Maps that is constantly evaluating driving conditions and finding the optimal route to the destination. It does this based on the vehicle's precise location but irrespective of the vehicle's velocity or time to next turn. The actual AI driving the car is trying to find a path along a route that can change suddenly and without consideration. It's like when your passenger is navigating and says "Turn here now!" instead of giving you advanced notice.