Photographic memory is the creme de la creme for brainiacs. A person opens up a book and looks at each page for a few seconds and has an exact photo image of it in their brain. Later, they can see an exact duplicate of those pages by pulling them up in their mind.  For U.S. Memory Champion Chester Santos, he can't count the number of times someone tells him they have a photographic memory. And each time, he gives them a polite nod and smile. He doesn't want to argue with the fantasy in their mind. Because for Santos, a photographic memory is just that. Pure...