Yes, but functional units are only around ~6% of the power consumption of a modern superscalar processor. And with Moore's law squeaking out its last few iterat

Yes, but functional units are only around ~6% of the power consumption of a modern superscalar processor. And with Moore's law squeaking out its last few iterations, that number will get even smaller. If you can remove a good part of that by using predication, then you actually win out on power and heat as well.