I only just managed to check that video out...
I was aware of that illusion for a while now, actually. I never gave it too much thought, probably because I'm more of a visually oriented person... But it certainly has its' merits as an illusion. It does well to distinguish itself from the vast ocean of monosensual illusions.
It's a more novel illusion and you're quite right in thinking about the ramifications of it. In short, though, all illusions are products of glitches and shortcuts.
For example, looking at
this for a few minutes will create serious visual artifacts and headaches. We use cues and draw conclusions from those cues. When something unexpected, like the double face phenomena occurs, our brain tries to fix it, per se... but it's not perfect.
