When I was first learning, a teacher who'd spent some time in BsAs told us something that made a lot of sense: that your torso moves first, creating a slight imbalance that makes your foot want to follow. Obviously you lead a turn with the torso, but you also lean to the side, forwards or backwards, and then the step follows with a bit of urgency.
Leandro Palou of Tango Soul, London, confirmed this in a class last year, and I gather that he spent many hours in his teens in milongas, and got all his basic experience there before dancing in Tango por Dos. Between dances in milongas partners tell you how you can lead better, where you're going wrong, and Leandro said that older leaders would take him aside and teach him. (I remember discussions whether dancers should comment on each others' dance at milongas, but porteñas don't hesitate to do it, and it's useful. If leaders take offence at a polite observation it might suggest a problem with more than just dance skills.)
Negracha was quiet last Friday, so it was a good opportunity to check what had happened to my torso movements: you wouldn't have time to think of such things when Negracha is busy. I realised it was something I'd partly lost. I decided to check the theory against video, since 'slomo' video is a great tool, and I chose Luisito Ferraris because I've enjoyed watching his videos a lot recently. Just 18 secs.
Well, it isn't as clear as I thought it would be, but his weight certainly stays right above his moving foot, and he carries his partner with him.
I found this by chance: an interesting comparison.
Junior shoots his leg out energetically and his torso catches up with it a lot later, that's clear. So what is he leading with? It looks as if he actually didn't lead her right step, she saw it. The dance that follows (here)is acrobatic, at arms length, and both partners are for the most part looking down to see what is happening. I'm afraid it doesn't engage me. They keep to the beat but it's hardly musical or an expression of the music. It looks no more than a breathtaking display of skill. Junior Cevila is one of the best-known post-Copes display dancers; Rachel Greenberg currently teaches at Negracha.
A bit more slow Luisito. Perhaps it doesn't disclose his secrets, but it makes it easier to see what he's doing. I wanted to watch that wonderful swirling movement again that expresses the feel of the music so well. There's a slight change in posture between leading forward and backward steps, and right at the very end there's a double time he clearly leads with his torso, by leaning forwards more. I found in BsAs, and to a certain extent in Paris, that partners expect to lean into each other more noticeably: you feel the contact more firmly. It makes leading more positive as there's a better connection. It also suggests an immediate trust.
Incidentally, MsH and Arlene, if you're reading this, a comment appeared after your comments on the video of Luisito I linked (here). I was amazed.
PS: Should add a correction. I mentioned feedback in milongas, but that's not correct. Feedback in classes and in the practica area where classes segue into milongas. There are other topics for the brief pauses between dances in a milonga.