It was never really shown, but it was part of the original development ideas. Haven't you seen the early gameplay movie which shows Rayman fending off the entire Rabids army by himself? (EDIT: Just remembered it also showed Michael talking about the gameplay while sitting on a window sill.) It was quite old in development, but it was sorta like that, except in areas which you had already cleared. The nunchuk and the remote were going to each act as one of rayman's fists, and you'd run around defeating rabids. Also, you were originally gonna be able to just jump on things like spiders and ride them.

Yeah, I was following this game since it was MENTIONED.