With each iteration, we gain experience. Experience with stories helps us estimate future stories more easily and more accurately.
You've just released your changes for some task. When you finish all the tasks in a story, it's time to take a moment. For example, when Chet and I wrote the Summarizer program in Test First, by Intention, it took us about an hour. From now on, we'll have a good idea of how long it takes to do tasks that are about that hard. And of course it's not difficult to estimate whether a given task is about the same size as the Summarizer, or half as big or twice as big.
This means ...
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