I would love to read the original article. Just as a viewpoint. It's important not to take every word or view printed anywhere as 100% accurate or appropriate in every case.
Interestingly on the lady's posture, i've seen top teachers pushing up below the lady's shoulder blades (should i be saying scapulae?? )to improve posture. This may be to encourage engagement of the thoraccic region.
Also, more controversially, I've watched top dancers and seen the ladies bending back from the waist. People keep telling me this is an illusion. In spite of this warning i keep seeing it.
I've had so much postural problem myself over the years (i don't mind admitting it) that i'd love to see the original article if it refers to the man's posture.
I've been to physios and actually done a few dance steps with them in an attempt to improve my own posture. I think it's working. Slowly.

I believe its important to note that..the body alignment of top Pros in competition, are, to some degree, exagerated.. its all about " Lines ", and the common mistake , is for the average student to emulate those positions.

Also, the hand position of the Man on ladies back , has now returned to an original position ( in the 40s ), on the Shldr blade .

One would think that this would restrict somewhat, the upper body of lady, from the extreme appearance of bending from the waist .

If this keeps up, there will soon be a majority of real people posting on this thread ...

I'm not sure what telemark means, but in a curious way, the comment has motivated me to pass on a little anecdote, just in case there are 'real' people out there with time to read it.
As i've already admitted, i've had so much trouble with my posture (maybe i'm worrying about it too much - wait! - so is my teacher) that it's become almost an obsession.
I'm guessing, but i presume other dancers have a similar problem - as soon as i move, the brilliantly stunning frame and "dancing phil" is replaced by "supermarket phil".
So here's a little something which, by pure chance, i picked up in the gym. Another person was having a session with a personal trainer doing lunges (you'll have to look them up) and shouted "no - don't collapse when you go down - keep your posture".
My ears pricked up so fast i nearly fell off the cross-trainer.
As soon as it was polite to do so, i did some lunges in front of the mirror and checked my posture. I do them every time in the gym now. It's great practice for this aspect of dancing (which of course is the most important for competitive dancing). And it's hugely repetitive, so it's more easily learned.
I firmly believe that the most important/difficult topics should be tackled straight away. Whenever i see a novice dancer fretting over a sequence of steps, i'm inclined - politely of course - to suggest they at least do it with good posture.

I am real person . . . . The use of lunges was recommended to me by a coach. Here is his sequence. Weight on Left Lunge Forward with right, Brush, Back with the right, Close. Switch legs and repeat. I'll do them to a few tunes and move on. I focus on tight core, shoulders down and tail bone down.

Edit; I should add on the lowering I think "up" with the head and chest. As opposed to lower/collapse

A point, which has been ignored so far,is AGE. The posture of normal every day use, is molded by time, and to expect the average person to attain the "posture" of top flite dancers, and to train them to that level, is beyond my comprehension. Yes, if you are taking a young person with competitive aspirations, then by all means apply the methods to " shape" that person.. but.. in perspective,the average social dancer, needs to be approached from a teaching standpoint from a totally different angle.

For those who are teachers on this site, if you are fortunate enough to have young students who are interested in the comp/medal test world , OK.. but , the bread and butter of most schools is the social dancer, and in todays dance world, expediency is the order of the day, and developing top lines, is not their biggest concern !

Clumsy,
Thanks for posting the lunge method you use. (I doubt you're clumsy if you can do those that way.) I'm 48. I've been working to improve my core strength for a few years, now, and I think I will add this way of doing lunges to my exercises. And, Terence is right about the issue of age, but - with work and dedication, those of us who are middle-aged and older can improve our posture and dancing.

Please remember that posture and shape are not the same thing. Indeed, many of today's young competitors with extremely "presented" shape have truly horrid posture.

Posture - in the sense of alignment - is something that all dancers should strive for, because it is fundamentally about making the dancing easier and healthier. Usually the faults are excessive curvature in the lower back, leaving the hips behind when moving forward, and/or pitching forward into the partner's airspace. These are faults no matter what one's goal in dancing, because they interfere with the ballroom concept of partnering and healthy body usage.

Shape on the other hand is primarily created in the upper back. And is optional for social dancers - really, far better not to have any shape at all and to simply align over one's own feet, than to fake it with curvature of the lower spine.

Finally, to the other person who recommended a forward placement of the weight; that's fine during some phases of action, but to actually move backwards while maintaining sound posture, it's going to be necessary to take the body weight to the back of the standing foot. Ladies (in particular) who try to take a backwards step while keeping their weight forward in the standing foot end up arching their back - which is to say, the only body part who's movement actually counts for anything (the center) doesn't move until far too late. The weight shouldn't fall back too early either, but leaving it forward too long tends to be a more lasting problem. Quality ballroom movement is characterized by smooth and continued travel of the center - no pulsing starts or stops. To create this, the body weight must similarly travel the length of the feet, with smoothly continuous timing.

If "Anonymouse" keeps posting parts of the article that started this debate, we will have the whole lot.

that would be plagiarism in bits and bites ...