Title bait, at its worst. What they created is a convoluted (if somewhat cool) way of retarding light from reaching the observer, thusly masking the event. The

Title bait, at its worst. What they created is a convoluted (if somewhat cool) way of retarding light from reaching the observer, thusly masking the event. There's no "time shift" or anything of that sort involved. Imagine I record an event and then replay it for you in a monitor, with a 20 second delay. Does that mean I 'erased' 20 seconds from history, or that I 'masked' the event? Nope.