I tore my AC joint in my should two weeks ago and had to use my left hand for everything. At first most things (like shaving) took forever but after a couple of days my dexterity got surprising better. It got me thinking, I wonder how people become right/left handed. I wonder if I could ever get as good at tennis playing lefty as I can play righty. I also wonder if they'll be more Rafa Nadal types (natural right hander but taught to play lefty) because being a lefty is advantageous in sports like tennis and especially baseball. Anyone know the science behind it?