I will argue it is an exaggerated break down of body mechanics of natural walking used as a tool to teach. A grounded dance resulting from holding the weight on standing foot as the other free leg steps forward or back, doesn't hamper the connection. You are perhaps talking about where some instructors teach sitting down and lowering on the standing leg, extending the other free leg forward and then pushing off the standing feet on to the fully extended in forward motion. It may be good as an excercise. To practice walking properly without bad posture. That could be an easier way to get people to start grounded walking. It is our walking mechanic is everyday life. It is exactly how we climb up the stairs. We don't fall into the next step when walking up the stairs. It is also how we balance ourselves. I see many dancers with bad habits of falling into the step or when they move, it is not clear.
It has become more popular now. I taken workshops from several different instructors where this get taught. Some are better than others at explaining it. I agree with the principle behind it. That principle is also used in salsa dancing. I suspect universal to any dance that is to be danced grounded. Putting it correctly into the tango walk when dancing is a more nuanced and longer detailed discussion. The weight distributio on the foot, forward weighted or back weighted, transfer of weight from toe to heel or heel to toe, etc. Easier to do it in person.
Tangochaos.com has also discussed this in detail with some animated illustrations.
I like how he walks. I see the walking mechanics in to be correct. I don't see chest projection in his dancing. It is a relaxed on his axis, well balanced walk with no unnecessary bending of knees. To walk that way with a partner takes plenty of practice for people starting tango as adults.
May be have different meaning of images that terms like "chest projection" and "leg projections" conjure up in our minds. I don't consider exaggerated forward leg extension while staying fully weighted on standing leg to be a projection (of intention). The intention can be projected by slightest (but clear) movement in ones body. The exaggerated forward leg is a result, when it gets taught that way. You are correct and I agree. It is not good to transfer the exaggeration into social dancing. To me "chest projection" conjures up images of how it was popular to teach "apilado" dancing when I started. It was taught as leaning into each other using the chest. Instead of correctly explaining forward weightedness when in embrace that causes natural lean. Leaning into each other is different than natural lean when weight is in the ball of the feet. When leaning into each other the point of contact is the chest. In that type of hold/embrace, if you start forward movement, the partner feels it first and most pronounced at the point of contact. Which is the chest. All actions done down below at the feet level are emitted through that chest contact. The leaning into partner dampens a lot of clarity in the rest of the body. While the chest amplifies it. Since chest it point of contact, rather incorrectly I was taught to involve and initiate movement at the chest. To me that is chest lead and chest projection. I abandoned that many years ago. It was a show style dancing embrace taken to the social dance floor. I don't see the leaning into each other that I am talking about in Ricardo Vidort's dancing. I see that as upright dancing in my books. It has the natural lean but not "leaning into". I seen others demonstrate and dance with that "leaning into each other".
Tango after all is about dancing in degrees
I suspect we are talking about the same things. The words are getting in the way. The meaning, the context and image "projection" conjures up in our mind is different. I have started to be believe that the contradictions in Tango result from trying different ways to convey same basic principles. I strongly suspect that there was probably no systematic break down and conscious attention paid to how body mechanics work. It wasn't needed. Whatever was explained was to the best of ability of what a good experienced dancer "thought" was happening in his or her body. I think with so many people dancing in different parts of the world, teaching Tango becoming means of making a living, the technique cleaniness demanded at competition level like mundial, etc has bought those things into more focus. With adult dancers coming from background in engineering, science, law, finance, etc more logic is being demanded of the tango instructors. The GA dancers had more time to refine their dancing. When dancing as much as they probably did, they unconsciously figured out a lot of those things on their own. Perhaps unconsciously. The learners today are expecting conscious competence in the way instructors are teaching them the movements. That is leading the instructors to consciously figure out and therefore many contradictions we see.
Also there can be more than one way to dance. We adjust to partners way of dancing. Again it is matter of degrees. How much adjustment needs to be made to have an enjoyable, pleasurable, well connected dance. There are also many wrong ways to dance. That hinder the enjoyable, pleasurable, well connected dance. We haven't started talking about the chemistry with the partner. Why we enjoy some partners more than others.