I have heard that sometimes contracts work best if they’re deliberately vague enough to handle future exigencies, but this assumes both sides operate in good faith.

The US as a whole definitely suffers from serious organization debt. I don’t know which political party is more guilty: there are a lot of people who get a salary paid by donors for a job that revolves entirely around keeping donors happy; “Beltway Libertarians” are famous for this, but it would be odd if only one party did it.