This technique is clever, and it is explained very well on the video.
However, it's not going
into my repertoire for a few reasons.
Too many contrived moves, too much patter, to long,
too much explaining required.
You can see this in the example videos when he is performing for
the spectators, as they look a little confused and the trick seems to go on too long.
(Although,
truth be told, the specs appear to be about as sharp as a bowling ball.)
I'll stick with a
simple center tear, simpler, faster, and similar effect.
But, three stars for a a well produced
video presentation and a clever technique.