Correct me if I'm wrong but isn't locality unidirectional? Two close points in the plane might by chance be encoded far away on the line if they're unluckily next to a seam.
My take is that they should allow height to be coded in too.
As a result one of the first things I asked them was "where are the corners?" and they confirmed my suspicions that they have "tilted" the cube slightly (the vertical edges are not parallel to meridians at the equator) and that a very rough approximate location for two of the corners is one is roughly in the great Australian bight on the South Australian coast line, and another one is roughly in the sea of Okhotsk between Japan and the far eastern half of Siberian region of Russia.
TL;DR. Yes, yes they do try to put the vertices in areas where their distortion will be least noticed.