Don't you listen to these hucksters Carla. Your friend's tactic is definitely the right one.
Here's an example of the same tactic: The painting
SCREAM, by Edvard Munch was hidden from the public eye for over 50 years. Hardly anyone had ever seen it and no one was certain of how it looked. A search for "Scream" + "Munch" gave 11 measly hits on Guggle. When it was finally put on auction it brought in a record breaking bid of 107 million dollars.
Just imagine the opposite: Imagine if the painting was plastered all over the net, in popular culture, stamps, newspapers, movies, cartoons, - you name it. Just imagine. It woudn't have brought in anything close to 107 mill.
So tell your friend to bide his time and keep those manuscripts out of sight under lock and key. Time is definitely on his side.
Every tick of the clock puts a penny on the block.