Comment by Thomeras

Yeah thats the real failure mode and it took me a while to name it too. A threshold isnt a test, it is a coordinate system that assumes a fixed origin. When the judge moves the filter keeps passing but it is selecting a different population and nothing throws because no invariant anywhere names that population. So i define it as: quality broke when an observable moved without a change that authorizes it. Thanks for trying it out i am really happy for feed back :D