RightBackAtYou is when you detect hypocrisy and then you act on this hypocrisy by imitating or mocking the hypocrite by acting out his hypocrisy yourself, to try and make a point.
For example: consider that someone tells you to stop insulting people and stop making inflammatory pages. But consider that the accuser (the hypocrite) insults people using words worse than you do, and creates worse or similar inflammatory pages (not practicing what they are preaching).
When the accuser (the hypocrite) tells you to stop insulting people, and stop making inflammatory remarks and pages - you go ahead and say something insulting and inflammatory and pretend to be them with a RightBackAtYou attached, to try and make the person do some self reflection and to show that your tongue is in cheek.
While doing a RightBackAtYou, you are simply playing a game with the hypocrite - mocking their world by trying to show them what their problem is - by demonstrating it yourself as if you are them. This allows the other person to see themselves in the mirror without needing a mirror - you are their mirror. Sometimes, they simply don't understand what you are doing and it may take about 6 and a half or so years before they begin to notice what game is being played. Because they are so thick skulled, they simply see you as a horrible person (without self reflecting and looking in the mirror at themself first).
This is only to be done if the person really doesn't do any self reflection after you've constantly told them to do self reflection. RightBackAtYou is an AntiPattern if you don't try alternative methods first, such as informing the hypocrite gently several times of their problems. If these first steps fail, there may be only one option to somehow get it through to the person... doing a RightBackAtYou.
Case Study
Consider someone in the tennis court hits the ball right at you with a sharp hard spike shot. They consistently hit you in the face with the ball.. and it hurts. You tell them to stop - and they laugh. They continue to do spike shots and hit you in the face. You tell them gently to stop, and they continue anyway. Then you hear the hypocrite chatting with someone about how tennis should be played cleanly and that it is a nice game, etc.
Two months later, you decide enough is enough. You start doing spike shots yourself, and hit the other person in the face several times. The other person starts to yell and complain hey this is not fair, stop doing that. Tennis is a clean game and you must play fair. You can't hit the ball right at me in my face!. Then you say RightBackAtYou, how does it feel?. Why couldn't the person on the other side of the court do some self reflection and remember that they were hitting you in the face? How can they be so ignorant of their own ignorance?