Well, there are other reasons why it might be able to keep the eye in focus than eye-recognition algorithms, if the photographer initiates the 3D tracking by pointing the initial point on the eye, pattern recognition may be able to do it well enough, depending on depth of field and such things. And as the electronics gets faster, and you have fewer gaps in the focusing array, 3D tracking should work better than it has in previous implementations.
If it did actually do animal eye-tracking, they'd no doubt say so. I suspect it's not doing that.