Midline Option is a great play when you are facing a very tough 3-tech DT.  QB reads this 3-tech and either gives the ball to the diving B-Back or keeps it himself as he replaces the 3-Tech who has pinched in to tackle the B-Back.  The PS A-Back goes into orbit motion but on the snap of the ball, comes back to attack the B-Gap and block the most dangerous player.