I wrote above (well, below, actually): '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'. This lean is slight, hardly something you can actually see in normal circumstances. Leandro Palou teaches that couples should stand one foot's-length apart, then lean together so their upper torsos meet. Of course height, posture and girth affect this, so it can only be a general rule. You hardly see it, but you feel it: instead of constant contact, you can feel constant, if slight, pressure, and you feel the need to maintain this pressure as something precious, even as a challenge. I rarely notice it in London: in London accidental contact from the torso down to the knees is more likely, which is confusing and uncomfortable. We are mostly taught in open embrace by stage dancers, and very rarely by dancers whose practice is 'milonguero'.
In normal circumstances you can't see this, but in abnormal circumstances you can. I came across this video in which it is exaggerated. This might be a useful classroom exercise, but it certainly wouldn't be practical in a milonga. & it probably works here only because the follower has a very supple back and hips, so she really reaches back instead of just stepping back.