in response to tips on arm styling. I've been teaching professionaly since 1972 and here are a few thoughts based on my experience. Firstly..there are not absolutes in styling. Anyone who speaks in absolutes should be listened to with "a grain of salt."
To me, learning to dance is, in essence, learning awareness and control of one's own body, so that feeling and emotion may be expressed however the dancer wishes.
In learning to dance, that is why most instructor's approach this area last in the basic elements of teaching.
We can think of our body as a torso with 5 appendages. (Head, 2 legs, and 2 arms). Fundamentaly it is normal to say movement begins in the torso or main body and then continues out, or is reflected in appendages.
Thus, arm movement should be generated from the body outward through the arm through each major joint in series, beginning with the shoulder then elbow, then wrist then fingers.
Most people feel uncomfortable when they first begin using their arms and hands in dancing. It is normal for most people to keep the hands fairly close to the body for as a sense of security. For most people awareness and control of the feet, legs and body need to be learned before concentrating on the hands and arms.
My experience has been that many ballroom instructor's have not really studied movement or kinesthics and what limited knowledge they possess is from copying others whom they like the appearance of.
Hence trendy styles are more often the norm than not.
One good way of developing hand and arm control and movement is by practicing the Ports de Bras (arm exercises) from ballet.
These simple arm exercises can usually be found in many basic books on ballet technique. By learning these movement one develops the muscles to use and control the arms in appealing ways and having developed the awareness and control can then easily adapt to any individual stying technique.