yup it's true....woo said it himself on one of the commentary tracks for the DVD.....if you watch the scene closely, they went left upon entering the lif and later exiting the lif, they went the other direction....so there really wasn't much to clean up.

more over, the whole scene before and after the lif is shot all in one take with one steady-cam !! only johnie to has top that with his openning for breaking news as far as HK cinema is concerned.