This. As a PM, this is great for communicating tradeoffs to clients and senior management. As a dev, this is great for communicating tradeoffs to PMs. And conse

This. As a PM, this is great for communicating tradeoffs to clients and senior management. As a dev, this is great for communicating tradeoffs to PMs. And conservative estimates of development time (e.g., the dev doubles the time estimate) result in solid, well-designed, thoroughly tested products.