What is Reddit's opinion of Impro for Storytellers?

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A further discussion on mantras can be found in Johnstone's Impro for Storytellers. Short version: repeating simple phrases like "I'm so happy" inside your head will lead to your character being more positive, or whatever choice you want to see. I've also found repeating an improv note ("Listen more," for example) reminds us to actively do that one note. Many times, focusing on one single note allows the rest to fall into place.