This is an old thread.
No one is saying to simply ignore the behavior. When it needs to stop, you step in and stop it. But stepping in won't stop it from ever happening again.
You can train anyone to be afraid of a punishment. That's not an accomplishment.
But the goal of GBD is more than just teaching kids not to hit or not to talk back. It's teaching them how to be kind and respectful - which is a much greater goal. It takes more time and maturity, and sometimes you have to wait for the maturity to learn the bigger lesson vs. the immediate action.