Sounds like he is using simple cubic environment mapping to project the textures on the sphere.
The point of the technique I used on this 'cube' is, that you can theoretically add it to any arbitrary shaped model. The result depends on the triangle topology of the object only.
As you can see the first version is a simple wireframe texture following the edges of the polygons.
The second one draws lines which connect the midpoints of the triangles.
The bottom versions are basicly combinations of the first two.