Will underachievers have to eat more beans?http://www.cnbc.com/id/101137659Tyler Cowen's new book, Average Is Over, apparently paints a bleak picture for American underachievers, a group which he thinks will eventually include everyone except the top 10 percent to 15 percent.it is possible that 90 percent of Americans will permit their wages to fall to the point where they have to eat beans.