Twisting in Wing Chun is different from twisting in Silat.
If you watch the 2nd form Chium Kiu on youtube, you will see that they twist the whole body into their pivots.
Silat however, twists the top half of the body. I am learning that that yields more options for legwork. The baset sweep is a good example. You have to keep your base and turret independent to sweep, as the top half creates torque. Maybe I can find some vids to show the distinction.