Imagine if he tried to do the things on his list, but failed. Would he be less happy? Probably not.
Of course, this is all assuming that he is truly the "completely satisfied" person that the article paints him to be. I doubt any person is quite so simple as that.
I think what you are talking about is where you did something and it didn’t work out for yourself.
edit: and of course, 'people who have hurt others' encompasses all of us, to greater or lesser degrees. I'm not saying that none of us should be happy with who we are, or that we should never admit that we think things turned out for the best, weighing the good against the bad. But surely most of us have some things we really would do differently if we had our time again.