CuplaDays comes in very handy as a rough guess or starting point for implementing and testing just about any reasonably well defined piece of code.
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It would be really neat if you could reduce all stories in an XP project to CuplaDays. Then velocity would be just the number of stories you could presently do per iteration. 40 more stories to go, 5 stories per iteration? 8 iterations. That'd be nice.

We can't quite do that, so some stories are CuplaDays, some are 2x CuplaDays, and so on. Many teams use IdealWeek''''''s, but same-o same-o.
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What's in the cup that a CuplaDays can't get out of your system?
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''I love it... if we ever get PlanningGame going here, I'll propose CuplaDays as the unit of measure (as opposed to I''''''dealDays/IdealWeek''''''s/GummiBearsOfComplexity)''
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alternate spelling C''''''ouplaDaze
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CategoryIdiom