Actual red-green-refactor TDD results in the simplest possible code to solve a problem, IME. Over- or under-abstraction tends to be pretty well instantly recogn

Actual red-green-refactor TDD results in the simplest possible code to solve a problem, IME. Over- or under-abstraction tends to be pretty well instantly recognizable when working with a well written test suite, and can then be easily and safely refactored away.