BLACKSBURG, Va. —Virginia Tech running backs coach Shane Beamer prefaced his answer with a warning Wednesday. He knew from experience that the message boards frequented by Hokies fans might “melt down” after he mentioned the possibility of dressing six tailbacks this year. Beamer even laughed as he noted “each guy kind of has a unique skill set,” one of his go-to lines in 2012 when Virginia Tech never settled on a featured runner.