The humble rock step is something probably most people have come across in their tango education very early on. It might have been taught, for example, as a way to change direction, or simply to mark time etc.
I recently saw someone marketing on Facebook his “wisdom” on the rock step. The photo shows a couple in embrace, their knees bent, and sinking down at the end of the rock step (by “end” I mean either the forward rock or backward rock). This immediately reminded me of the amusing experience I had during my first and only trip to Buenos Aires in 2009. In a single day, I was corrected on the rock step by no less than three different teachers during my private classes! On each occasion, I was reminded that, as a lead, I should be rising (and hence as a couple) instead of going downward. The three different people consisted of a globe-trotting well-known teacher, a well-respected milonguero and a young teacher for whom I have a lot of respect for. Through this, together with my subsequent experiences on the dance floor, I am convinced of the correctness of what I was taught on that day.