But what the authors of The Levity Effect mean by "levity" is really a sense of lightness. It's less about being funny and more about being able to have fun and see the humorous side of everyday situations -- especially difficult situations.
A few minutes of respite from a difficult task can save hours of wrestling with a problem or situation. In those high-pressure times, why not gather your whole team together and give them a group break?
Exchanging holiday gifts in the office can bring as much angst as joy to both gift-giver and receiver. How do you ensure that everyone gets a gift of equal value? How do you ensure that everyone gets a gift?