Narrative form is the main agenda item.
This has a number of effects. First, it means the proposer has to think deeply about their proposal. As Jeff Bezos, the CEO of Amazon, put it: “The reason writing a good 4 page memo is harder than ‘writing’ a 20 page powerpoint is because the narrative structure of a good memo forces better thought and better understanding of what’s more important than what, and how things are related.”
But there is a deeper reason why this technique is powerful: it commits people to deciding what they think before learning the opinions of others. They have the space to bring their diverse ways of thinking, reasoning through the weaknesses and strengths of the proposal, before discussion. This reduces the risk that diverse perspectives will fail to surface. And even when discussion does start, the most senior person speaks last, another technique that protects diversity of thought.