Why the long route buys time
The fairest comparison holds tanker size constant and changes only distance. A long voyage commits more cargoes before the disruption even begins.
Longer route, more overlapping cargoes
The blue line shows ships already underway. The amber line shows how many fuel-days are already afloat. Both are labeled directly at the current route.
What is already on the water
The sea lane below shows the same inventory as moving cargoes. That is why a far-away importer can keep receiving fuel after departures stop.
Three things your friend should notice
The point is not that distance creates fuel. The point is that distance shifts some of the storage system offshore, onto ships that are already underway.
1. Distance creates overlap
A short route only needs about one cargo in motion at a time. A longer route needs several cargoes overlapping across the lane.
2. Overlap becomes inventory
Those overlapping ships are not theory. They are real fuel-days already purchased, loaded, and sailing toward the importer.
3. The cutoff hurts later
When departures stop, arrivals continue until the last already-sailing tanker docks. That arrival tail is longer on long routes.