Hmm...that, actually doesn't make sense.
Imagine you're just a floating sphere and there's a few structures nearby for reference. A random direction is picked from the NESW plane and you're pushed in it. Since nil space is anisotropic, how much do you go up or down? If NESW are relatively interchangeable, you could be interpreted as being closer to NW and going up, or closer to SE and going down. Or a middle and staying vertically still. That's kind of a paradox, really. I would assert that NESW are also anisotropic this way.
Does it mostly count based on how much you actually turn once you start travelling? I mean, it can't really, because the bird immediately goes up once it starts going on the path in the explanation video. But then it goes in all directions, and as long as the turn is counterclockwise, it goes up. Aaaaaaaagh (/─_─\)
Are you just naturally N when you start arbitrarily moving and turn from there