I disagree.  This gave the offense a clear advantage in recognizing the defense.  They no longer had to recognize formations on the fly.  They knew the signals. Even if they only did it to 2 teams each season, that's 4 games / wins that should have been losses.  Their record for the last 3 years would have been 8-8, 6-10, and 10-6. If they didn't use the info to win the actual Super Bowls, they most likely used it to get there.  That's disheartening for any fan.