In the grasp

Could someone tell me, if there was ever a rule ,that if a quarterback was in the grasp of an opposing player , the reffs were to blow a whistle instead of the quarterback being tackled to the ground?? If so ,what happened to it , was this just something the league was kicking around in the past? I remember the term , " in the grasp".

Copied from the CFL Rule Book, Rule 1 - Conduct of the Game, Section 4 - Dead Ball:

• When the ball carrier behind the line of scrimmage is firmly in the graspand control of a tackler to the extent that the ball cannot be thrown