I've noticed it a few times as well. One thing though is that it looks like every region has a connection to every region it is adjacent to, so even if it was switching over to the lattice system randomly and then switching back, there shouldn't be any functional changes.
Looks like it doesn't it?! Seems the system is exactly the same except they drew ome lines between regions :s
Topic here if you want : https://forums.station.sony.com/ps2/index.php?threads/can-see-lattice-on-esamir-and-amerish.136035/