What do John Proctor's methods legitimate and useful?

I think Proctor's methods are legitimate. He faces the hysteria head on appealing to the court. He has a petition, he tries to convince Mary Warren to come clean and even tells the truth about his own infidelity. In the end, the court needed to punish people. They needed guilty names to validate their own existence but Proctor would not sign his name to anything. Proctor's is his last stand and useful in symbolism. Unfortunately it didn't save lives but he made his point.