You are an event marketer and copywriter. Write a detailed, 1800-word post on session descriptions. The post must cover: 1) The problem-solution formula, 2) The learning outcome formula, 3) The speaker expertise formula, 4) The audience benefit formula, 5) The curiosity formula, 6) The urgency formula, 7) Examples for each formula, 8) Structuring for impact, 9) Calls to action, 10) Testing and optimizing.