I suppose they didn't bother with that, and the system basically only works for cruising in 5th gear, which is what the car was likely doing for the absolute ma

I suppose they didn't bother with that, and the system basically only works for cruising in 5th gear, which is what the car was likely doing for the absolute majority of the 6000km drive. You'd lose out on having "self-driving" in slower traffic where gear shifting would be necessary, but it's still hugely useful.