The following information is published with ROUNDALAB's permission from the ROUNDALAB Reference Manual compiled by Richard & Jo Ann Lawson, 1987.
Don't Bounce
Brian Bassett
One of the first rules in dancing is DON'T BOUNCE up and down while executing various dance figures. The rule rates right up there with "Don't look at your feet," and "Don't dance on your toes."
Beginning dancers, once they have become comfortable with their basics, find the need to relax and enjoy dancing the figures they have learned. There is nothing wrong with relaxing and enjoying dancing as long as it is done is such a way to incorporate proper body mechanics. Fun and enjoyment are often wrongly translated to mean a display of extraneous body motion... BOUNCING being the most common.
The first place you will probably notice BOUNCING (dancers, in your own dancing - leaders in your dancers' dancing) is in the VINE dance figures. This VINE figure, whether it be a regular vine with both partners crossing in back or in a twisty vine with the Man & Woman crossing in back or in front at opposite times... suffers most in the execution and appearance when dancers BOUNCE their way through it.
You will notice that the crossing steps will take on the dance-style of the LIMP with an exaggerated downward motion. You will also notice that the sideward steps will be dances with an exaggerated upward motion, causing the dancers to rise on their toes. Put these two exaggerated motions together and the dancers will "bob like corks" in the ocean.
Sure, it's fun... but "fun" at the expense of proper body mechanics, and rather comical to watch.
A responsible teacher should explain to their dancers that the legs should act as shock absorbers while dancing. Knees flexed (bent slightly, not a crouch) all the while a dancer is dancing will eliminate Bobbing or BOUNCING.
While dancing, you progress around the floor in various directions and often turn right or left even while in one spot... both these actions, progressing and turning (also pivoting), are more difficult to execute if your body weight is directed either straight down or straight up. So for more comfortable, pleasant to watch dancing, keep those knees flexed and DON'T BOUNCE!
Roundalab Journal, Winter, 1987