Imagine displaying a card face up in the middle of a spread of playing cards held in the hands of the magician. Then with a gentle shake, the card changes to the Chosen or even thought of playing card. The change is visually striking, happens in the open while isolated in the middle of a spread.
You will be able to add this into your arsenal of sleights minutes after learning it.
Braden also teaches you how to incorporate this into a Red Hot Momma/Chicago Opener style effect so you have a context to practice this wonderful piece of impromptu magic.