I contend that tests need cover functional and non-functional requirements. Everything else is to some degree optional. Of course given no formal requirements,

I contend that tests need cover functional and non-functional requirements. Everything else is to some degree optional. Of course given no formal requirements, all that is possible are tests of the technical implementation. Regression errors will still be inevitable for customers and stakeholders, despite the "programmer" being able to claim his or her tests passed. We need to find a way to stop kidding ourselves and find a way to test the right thing.