Petroleo does a step that I have only seen one other milonguero do. He stands on one foot, pivots it, and begins to move sideways while the other foot is dragging along, or hovering over the floor. I may not be describing it well, but it’s something like what James Brown and Michael Jackson do on stage. He moves by pivoting from the heel to the toe of the foot he is balancing on, and it gives the illusion that the person is floating along on one foot. Here is Petroleo from an old film:
Petroleo is moving to the left by quickly pivoting from heel to toe on his left foot (1),
with his right foot dragging behind (2)
And here’s El Gallego displaying a similar technique while dancing milonga… but he takes it to a new level:
El Gallego moves to the right in a circle, pivoting only on the heel and toe of his left foot. He takes Alej
completely around,360 degrees, with his right foot floating above the floor the entire time. El Gallego
is the only milonguero I’ve ever seen do this in a milonga.
Finally, here is a series of Osvaldo dancing with his wife Coca in Club Banco Provincia.
Osvaldo is on his toes, doing Petroleo’s small quick side steps.
Most people today would probably consider Petroleo’s style, a Model ‘T’ Ford in a Lexus world. Osvaldo is probably the closest thing to Petroleo's style I’ve seen in the milongas today. He and his wife call their style orillero, (meaning from the edge of BsAs). It’s slower, and more sophisticated than the old tango, but there is certainly some Petroleo in there. And here’s something nice: Osvaldo and Coca used this style to win the world championship of tango in BsAs in 2004!