I saw your question for Steph and I can answer that for you. Yes, Steph is on the set of every film each and every day during every shot to make sure that things stay on course. She keeps a tight reign on the creative side of her works and wants to make sure that no one changes anything without her go ahead. Especially now with the filming of Breaking Dawn, things are getting more intimate between Bella and Edward and Steph wants to make sure that the films are kept PG-13, the same way she wrote them. If she wasn't on the set, she knows that they would end up being R ratings and she doesn't want that to happen.