For the action of "Ride Tram to Santorini," does it not benefit from repeat completions? (I could see the tram as having a fixed speed. There is only so much experience can offer!)
Correct. This action will be changed in future versions so it's a short "start the tram" action, which triggers a fixed time event. So it'll be more obvious that it doesn't benefit from familiarity (and why).
