Writes John Clayton, a long time veteran sportswriter:
For the past three decades, many coaches have copied Walsh's script idea. It made sense. As teams got to the end of the week, coaches put together a script that would keep defenses guessing. The plan stressed execution. Quarterbacks and offensive players had a couple of nights to study the script, visualize the successful plays and start the game with a positive tempo.
Fast starts were important to Walsh. He built his great 49ers teams with the idea of getting two scores in the first couple of drives. Working with a 10-0 or 14-0 lead, Walsh then made sure he had enough pass-rushers to pressure a quarterback into mistakes and take opponents out of their rushing attacks.
Here were the three reasons why this strategy has endured - despite, as Clayton notes, more recent blitz-oriented strategies to combat them.
1. Promotes confidence and calmness among the team.
2. Provides the opportunity to specifically probe the opponent's responses
3. Creates the ability to train, drill and rehearse