All competitive cat sailors use their body weight positioning to advantage! Whether or not you call it "kinetics" or whether you just call it "trimming" it is all basically the same, with the same or similar results.
When sailing downwind, with a following sea sailors position their weight forward to depress the bows and lift the transoms, this alows the hulls to travel more efficiently through the water with less "transom drag" and it also helps the boat better to "catch" waves. A competitive sailor will always try to move his weight contiually on a cat (whether they are inboard or on trapeze) to attempt to maintain the hull(s) at a stable angle with the minimum of pitch (pitch produces drag) similarly, particularly on trapeze, the weight is constantly shifted in towards the gunwale and out at full body stretch to minimise the heal of the cat with the minimum use of, dropping the mainsheet and pullimg it back on again. These are some of the obvious ways that sailors "use" their body weight in order to "get more" out of their boat. Some may call it just obvious trimming techniques, while others could call it the use of kinetics, which ever, it is apparent to most sailors of cats that the correct use of body weight positioning on a cat has a far greater overall effect upon the different in its performance than it does on any monohull, regardless of what it's called.
Darryl