I agree that the proof is pretty much handwaving, actually, but I still think their underlying conclusion is valid: Our efforts into optimizing languages shoul

I agree that the proof is pretty much handwaving, actually, but I still think their underlying conclusion is valid: Our efforts into optimizing languages should focus on making programmers more efficient, before hardware. (In other words, programmer time is almost always more expensive than processor time.) Also, I think most things in computing called X's Law are not entirely serious, these days.