“Scramble drill” wasn’t a phrase used much in last years Pittsburgh Steelers’ offense. Not when the ball comes out in a league-quickest 2.3 seconds like it did with Ben Roethlisberger. Not when Roethlisberger became almost entirely a pocket passer, a clear departure from what he was over Act I of his career. Now, the Steelers have a group of mobile quarterbacks, ones willing and able to extend the play. And rookie Connor Heyward is learning to keep his head on a swivel for where the quarterback is going. He spoke with reporters following today’s practice about gaining chemistry with quarterbacks once the play breaks down.