reference?
It's quite simple, really. The Circumference (distance around) of the Round Earth is 24,900 miles. The Diameter (distance across) of the Flat Earth is 24,900 miles.
Cutting the circumference of the Round Earth in half, traveling from the North Pole to Antarctica in the the Round Earth model will take you 12,450 milesl.
Cutting the diameter of the Flat Earth in half, traveling from the North Pole to Antarctica in the Flat Earth model will take you 12,450 miles.
Therefore, the distances North to South are identical between models.
actually, it would be further in a round earth model because it reaches all the way around. Where as in a flat eart, it is thus stopped at the ice wall.
Cables don't travel over Antarctica.