The Relationship Between Testability and Deutsch's Easy to Variate Criteria

Popper's epistemology could be in a certain sense thought of as an attitude. If you have the attitude, I am trying to move my theories towards being empirical so that it's easier to come up with experiments and you're being a parrot, this is why empiricalness is central. As you make your theory hard to vary, you are moving towards the goal of being testable. Even if it does proceed testability, it's deeply tied still to testability. And likewise, if you're just going to ad hoc save your theories over and over again, then your theory is no longer refutable or testable anymore.