Mirroring can backfire around people who want to dominate instead of build rapport. Your boss who takes you aside and wants to put the “rivets to you” isn’t going to respond to mimicry. In fact, trying to mirror him is likely going to make matters worse. In most cases, a dominant boss who displays dominant body language is not interested in employing someone equally as dominant. The default condition, or rule of thumb, to working with dominant people, unless lead otherwise (by your boss), is to show submissive postures. Fight dominance in superiors with submission, that is, hold your legs together, arms inward and hands on your lap.
There are a few exceptions when dominance should be fought with mirroring such as when we wish to rise in ranks by building equality with our bosses or wish to compete head on with other dominant people for positions or perks. Other times a boss will require someone specifically to hold a position of dominance, so will be looking for someone who reminds them of themselves. Bosses will seek these people for higher management. Lawyers can and should posture dominantly to each other. For them it can work to thwart challenges. It is expected in lawyers, and in other professions, to fight fire with fire, but in normal circumstances, mirroring will only raise the hackles of others further.
A second related instance where mirroring is not advised is during confrontation and aggression and this defines our second rule of thumb which is to avoid mirroring in hostile situations. To avoid a full blown fist fight, diffuse aggression with submissive postures. This doesn’t mean you can’t come out the winner, it just requires a different approach. More than anything it requires defining winning in a different way than traditional. In other words, walk away unscarred, alive and you’ve won!
The final caveat to mirroring is to use it only during win-win negotiations and avoid it during win-lose negotiations. Win-lose situations are when one side clearly wins and the other looses. Poker is a win-loose situation where one person wins the chips directly from another person, whereas win-win situations happen anytime prices have room for flexibility such as negotiating on the price on a piece of carpet, a car, or a house, where once the price is agreed upon both parties will benefit. Other arrangements that are win-win are partnerships that involve no money at all, but rather an equal input of labour. Therefore, our final rule of thumb is to only use mirroring when there is give and take involved, or when the task includes cooperation beneficial to both sides. The caveat, of course, which was mentioned previously, is that all mirroring must always go unnoticed for it to be effective.