But if we change those, then it's also a change for the user, and they should be made aware of it, and the unit tests should point it out to us.
For the intended usage of this function, the precision doesn't matter much, and only the ranking is really relevant.

(And, regression test work partially as developer documentation, I was going back through the git/bzr history, to figure out what the expected old behavior of HuberScale was, after I started to make some changes. Unfortunately, the history search was unsuccessful. If I had had some regression numbers, I would have chased fewer dead-end guesses.)