The expectation was wrong and the anger was right. It's the target of the anger that's wrong. That's why self-control and kindness were the better option. Further, they're more likely to get what you want out of the situation. A situation you've already invested a lot of effort into. The rational choice is doing what works. This also prevents extra anger. It's best choice for your emotions, too, even though they won't let you see that in heat of the moment. Hence, understanding that in a non-angry moment to start making a habit out of controlling and directing anger properly.

Although, I went further to not get pissed off at all as many times as I could for typical bullshit of corporations. I mentally relax, do other things, and am ready to focus the second support answers. I do something similar to what was advised. You'd be surprised how much good service I've gotten from especially Comcast but also others. There's, as author says, people that just don't give a damn. Most are happy to help and happier to be appreciated. Which is sincere on my part by the end of it so long as they put forth effort on the problem. :)