what I'm telling from the beginning is that sending back the leg diagonally (what I see too often) is not the most elegant way. ... it would be too difficult for an average dancer to do it properly.
I don't know if this is part of the language barrier or it is actually your true attitude, but what is happening here is that you have a
personal preference. You like the look of a certain way. You define that as being the most elegant way. (That's debatable in itself since beauty is in the eye of the beholder however, it is perfectly valid for you to feel that way and have that opinion)
Because you have a
personal preference (and can I emphasize PERSONAL?) based on what you like to
see, you are saying all other options are "wrong" or "incorrect."
That is simply not the case. "Wrong" and "Incorrect" are not the correct words to use for what you are expressing. So maybe this is a language issue. It is simply not true to call other styles "wrong". It is not true that doing them the way you don't like to see them means doing them "incorrectly".
These are not proper uses of those words.
Your view and opinion are
subjective. Words like wrong and incorrect imply something that is
objective. (If you aren't sure of the difference in these terms in English, you should look them up because they are at the heart of this whole thread)
There is no objective measure when trying to define one style by the form of another style, and even less measure when trying to define "correct" using rules of another
dance. It would be like saying Expressionism is incorrect or wrong because it doesn't look like Impressionism. Or that the Impressionists were "wrong" because they don't look like DaVinci. You can argue that you like DaVinci better. You can argue that his painting are more realistic. YOu can even say they are more elegant. But you can't call the later movements "wrong". Picasso isn't "incorrect" just because he broke away from proper form and perspective or because his painting aren't as "pretty" as DaVinci's.
In addition.. you seem to be saying that the Argentine Milongueros, who are supposedly what "Milonguero style" is named for (and who are also the grandfathers of all that came after them in AT) are doing milonguero ochos
incorrectly. That in fact, they are dancing Argentine Tango "wrong".
That makes NO sense!
How can the people who invented a style or move (or dance) being executing it incorrectly? That's like saying Lutz in skating is "wrong" and shouldn't be done because the guy who invented it was basically doing a Flip "incorrectly".