Dear D. Seattle,
We all procrastinate from time to time. I, for example, received your e-mail in the spring of 2007. Forgive me if in the interim you have solved your dilemma, but it is possible that my answer will still be useful.
I think we can postulate a utility function along the following lines: having a Christmas tree up during the Christmas season brings positive utility, but diminishing marginal utility over time. After a while, the marginal utility is negative: the tree becomes an irritation, offering neither use nor ornament.
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