On Sunday’s, 125th Street was a virtual fashion show with men in suits and Stetson hats. He would later work for Ralph Lauren, and to say that he was preppy would really miss the point. The young man is African American designer. In this way, Brooks Brothers has, through its business plan alone, revealed to us all the 15 schools in America most infested by unbearable preppy (or faux-preppy) Brooks…