To say that they are different spectrums doesn't seem right. Our thinking is more cohesive. Logic and feeling are, and will always be, inseparable.
I agree, I also would like to repeat that the relation of logic/rationality and feeling differs from person to person, largely based on the strength on their functions, for good reason.
I have had times in my life where I threw my rationality out of the window and the results of that weren't very good. Why? Because I don't have a strong cognative function capable of replacing my rationality. So for me, rationality is extremely important in relation to feeling. Through rationality, I am capable of adjusting myself and fitting into society.
A Fe dominant will learn through experience how to wield that Fe even when they are hurt the most and not let it loose control of the situation. Something I would never be able to do.
However, all that said, there is also such a thing as unhealthy use of cognative functions, the ENTJ example is one of them, me throwing rationality out of the window is also a good example. This unhealthy use should never be "rationalized" or deemed appropiate. It often does, the world is far from perfect. But if there's anything we should strive for, is to not allow that to happen.
After all, we're herd animals, not lone hunter-killers.
So, an eye for an eye method of teaching someone a lesson, although it may prove to be effective, is not the best method of teaching in my book. We should strive to put ourselves above that and find better, more humane, ways of teaching.