Keep Calm and Game On

[Reinha]

I totally agree with you OP, and I'd like to add that raging at strangers is avoidable in most cases. Any content can be done with a premade party where you know everyone's skill level. If strangers are playing so badly that they are ruining any chance of success, it is of course their fault you can't clear the instance at that time. However, getting angry is a two-step choice. First, you (the general "you") choose to play with strangers and risk things not going smoothly in order to get a negligible DF bonus or to save time in finding a party. Second, you choose to get mad if things don't go smoothly. Adults have enough self control to keep their emotions in check in unpleasant situations, I hope. Those strangers are not to blame if you get mad because you have the options to avoid it. So indeed as the OP said, if you're in a bad mood because of bad play take a break from the DF or even the game. Unless you really enjoy being angry. Carry on pugging in that case I guess.

This video pretty much explains the scientific reasoning behind this.....

That's pretty spot on.