Your post is very good and matches the way I feel very closely. ++

If it's truly a one-off and you never have to maintain it, style isn't as important as completeness and correctness.

Agreed. But I would like to add that I don't expect code I get to see to be a one-offs, and criticize all style flaws in code I'm asked to comment on.

In other words: one better not bothers others with one-offs.