Coming from one of the worst environments since my parents divorce, I was in desperate need of help. I had just been thrown out of my high school for acting completely inappropriate, and having terrible fits of anger.
Not a single one of us can go through life angry at others for not handling situations the way we would have handled them. I can't possibly cope with debating each and every person I disagree with -- no one can.
Obviously all emotional reactions can't be eliminated by a mantra -- nor would we want them to be, but my informal experiment from years ago taught me that anger, though it may feel unavoidable at times, just might be avoidable far more often than we think.