Fencing is not something that you practice, it is not something that you learn. It is something you are taught. The role of the teacher is very important.
Tango, however, is something that you learn. There are certain things that the teacher can only ask you to do. There are steps that you have too make on your own, conclusions that you have to make, realisations that have to occur.

Indeed. So far, the longer I’ve danced tango, and the more I see of it, the less influence I think good, bad, or indifferent teaching really seems to have in comparison to the motivation and mindset of the student, plus sheer chance. I don’t think that’s any excuse for anyone not to do the very best they can, but I’m starting to think that the student’s self-direction is overwhelmingly more important in practice.
Mind you, I wouldn’t say that it _has_ to be that way. I can’t say that the teaching approaches I’ve seen have been particularly sophisticated. Some have been much better than others, but there’s probably enough room for improvement that teaching _could_ have a much greater influence than it actually does. You can’t have a realisation for someone, or take the steps for them, but you can at least ask them appropriate questions and tell them stories about it happening to someone else, so that they know it’s out there and have some kind of a map of where to look and what to do with it.