If my memory is correct, in Dempsey's book he talks about shovel hooks and the 'shoulder whirl' when in close. Try and throw a short hook/uppercut or to 'whirl' your shoulders without turning your hips.

And something to keep in mind, the hip rotation isn't like something you would see on a dance floor. It is in no way exaggerated. Your are turning your hips through to the center line of the body so sometimes- when you jab, for example, with your left hip and shoulder already well out front- it is a minimal motion. It is, however, a sharp and violent motion.