The bottom right area of the last image example makes me wonder...
If you meant something else, could you explain it a bit clearer?
Elsewhere in the thread I repeated the experiment on one of the images with resynthesizer GIMP plugin and got very good results too, but not quite as good. Of course I could probably have chosen an image which would have appeared to produce equally good results...
Though I'm not saying that it's not real. It would dumb for Adobe to make up such an impressive video.
My guess as to how this works is that it looks some distance in from the selection edge, and then repeats that outward (or inward), but matches up the edges to the selection. You can see it in the deleted road where the 'desert' on the bottom right of the new area matches the brush to the left of it, but the rest matches the brush to the top and right of it.
It's like creating a seamless tiling background, except instead of doing it in a square, it does it in an arbitrary selection path.