WCS is indeed a slot dance. The man is normally either in the other end of the slot, or immediately next to the slot so that the woman can pass by him. Her assignment, should she choose to accept it, is to get from one end of the slot to the other, preferably doing something stylish in the process. The man either leads her down the slot, or starts her down the slot then blocks her path, forcing her to go back to the end she came from. There are, of course, various turns, spins, fancy footwork and such associated with these manouvers.
Individual styles vary widely.
Most of the finalists at the US Open Swing competition have radically different styles. There is a lot of leeway for the follower to improvise and add styling and syncopated footwork, typically as she turns around at the end of her slot. Although there are turning figures, they still keep the woman on her line. The tempo is 28-32 mpm. The style is very casual and sometimes overtly sexual.