> One easy way to demonstrate how difficult it is is to have a cursor appear at the point of gaze. You're vision "chases" the cursor away from your target like

> One easy way to demonstrate how difficult it is is to have a cursor appear at the point of gaze. You're vision "chases" the cursor away from your target like it does a floater. That sounds like a slight miscalibration of the eye tracker. Assuming perfect eye control, if the tracker estimates your gaze slightly incorrectly then the cursor will always move away when you try to look at it.