"The gentleman starts on his left foot because the lady is always right."
This tired joke gets trotted out at the start of many introductory lessons, but there's some truth to it beyond getting leaders off on the right foot and the followers comfortable.
Partner dance is an inherently asymmetrical practice. There are the obvious asymmetries: we connect to our partner's back with one hand while raising the other out to the side, we often turn our head's slightly to the left, we travel only counterclockwise around the room.
But there are some asymmetries that don't make quite as much sense in a dance like tango, where we supposedly have the ability to step in any number of directions. These limitations can have lasting impacts on our dance and our bodies.
1. Leaders are likely to begin to a phrase stepping side to their left
2. Leaders will be more practiced performing lapizes as an embellishment on their left sides to precede this step.
3. Leaders will spend more time bearing weight on their right leg to perform these actions and therefore develop more stability on that leg.
4. This is a handy development since leaders are more likely to perform molinetes to their left (the open side of the embrace), balancing on their right leg to perform lapizes and enrosques, placing even more emphasis on the strength and stability of the right leg.
Followers develop the mirror image of this: greater comfort performing lapizes and molinetes to the right.
This might not seem like a problem immediately- you're developing greater skill where there is greater demand under the circumstances. From a wellness perspective though, this asymmetrical development can cause imbalances that carry over into your life off the dance floor (our dance is primarily walking, after all).
And on the dance floor, we sometimes perform less practiced actions by our own whims or the demands of floorcraft, with predictable results. The movements we have not worked on do not go nearly half as well (for example: leaders, try performing any sort of footwork while a follower does a molinete clockwise around you).
Besides being physically limited by our repeated actions, we also develop mental aversions to performing certain actions, limiting our creative capabilities. On a lesson recently, I asked a leader to lead weight changes from right to left after stepping forward with his right foot. He continuously did the opposite and was unable to understand why he couldn't do it, but the answer was simple: he had conditioned his body to only do it in one direction in that context. Something similar happened when I worked with a follower on her boleos with her right leg- they weren't led nearly as often and so she wasn't ready when they were led.
By failing to train both sides equally, we limit our ability to fully dance in all directions and express ourselves in addition to creating physical imbalances in our bodies. So what can we do? Identify those actions that only get performed on one side and train the other- who knows, you might find some interesting figures along the way.