Ah, I thought he wanted to go in the opposite direction: Set the Estimate, then log actual time, and then when a subtask is complete reset the estimate to be whatever the actual is. This results in a dynamic parent estimate that's refined as the task progresses. Compare that to what we do now, which is to create a static estimate which is used to compare with Actual over the lifetime of the project. It's a valid (and valuable) business case to have both mechanisms in place simultaneously.
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