This probably works for someone whose brain isn't always in "hyper" mode. My eyes - and mind - get bored when moving at such slow speeds as that dot, and my gaze flickers around the rest of the face while following the dot's movements, so the weakening of the morph was minimal, if it happened at all. What I'm trying to say is this illusion only works on people who can focus very hard, and whose eyes have the capability to stay on a set path of focus. Mine do not.