From wu-jing.org (also posted on Tron's site).
As a world-class martial arts director, Yuen Wo Ping has also directed many films, and will be helming Disney's big-budget Snow White and the Seven Shaolin Warriors in the near future. Yet, he draws a clear distinction between the two jobs, "As a martial arts director, one must not be to finicky down to minutest detail and neglect the essentials. Martial arts choreographer is but one of the production crew, what one choreographs and how one goes about the choreography should be approached according to script requirement rather than according to one's liking or mood. It could add an extra zest to a movie when the choreography goes hand in hand with the production, but would be redundant otherwise." Yuen Wo Ping always firmly maintains this principle while trying to bring out the differences in each movie.
On the especially exaggerated scenes in productions where people could fly or burrow underground, Yuen Wo Ping ascribes them to being penny wise and pound foolish, "The most important aspect of Chinese martial arts is the chivalrous spirit, we cannot simply stage a martial arts scene because it's in vogue, for no matter how eye-catching it is, it simply won't click with the audience."