We are concerned that short term execution difficulty represents high risk to 2011 and possibly 2012 earnings.

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But there are many mathematical combinations of difficulty and execution that produce competitive scores.

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In diving competition, scores are earned on the basis of two criteria: degree of difficulty and execution.

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The Obama team, unfortunately, has neither of those, so their degree of difficulty in execution is much greater.

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The difficulty lies in execution.

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That was supposed to balance the difficulty by also encouraging more consistent execution.

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Gymnastics scrapped its perfect-10 high score in 2006, replacing it with one that was supposed to remove some human error by instituting one score for the difficulty achieving certain moves, alongside a second, more subjective score for execution.

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