Angry writing is often very ineffectual writing, when it focusses attention on the writer's emotion rather on the substance of the complaint. Oftentimes it is hard to tell why the person is even so angry, because the prose is saying, very loudly, I AM ANGRY. Needless to say, if you aren't outraged by many things every day, you aren't paying attention. Anger itself is legitimate, but what I am talking about here is the rhetorical power of calmness.
If you are having an argument with a very angry person, you can often get the upper hand simply by remaining calm. You are going to be in much more control of the situation than the angry person is, because you are in control of yourself and the other person isn't. You can easily make the angry person more angry, if you want, by pushing even more of his hot bottons, or you can use your calmness to de-escalate the situation. Of course, the angry person's anger makes her seem more powerful (and sometimes the angry person is actually more powerful), but your calmness can be even more potent.
So it is with prose debates. When I was a kid (a strange kid I guess) I would read outraged authors writing in to the New York Review of Books. Usually, the madder the author seemed, the easier it was for the original reviewer to compose the rebuttal: "Yes, I see that the author is very upset, but let's look calmly at what I said in my review...." It always seemed best to win on "the facts" than on emotion.