Entertainment information published at the time - such as in an entertainment magazine - stated that Mitzi Kapture, the leading lady for this movie, learned some sign language for the role (obviously). Furthermore, the article notes that Ms Kapture said she didn't want to learn "too much" sign language for the role, seeing that her security-guard character was supposed to know only a little sign language. Of course, one can say that one can learn a lot for later and show just a little for now onscreen - just the much that the project needs. But maybe "that's not being honest with the character," as the actress Kate Winslet stated (in an interview for an unrelated project). And maybe one's intense training will keep slipping out during filming, extending production with needless "take" after needless "take" ("No, dear, you can't keep inventing American Sign Language on camera. Your character's not THAT versatile and, besides, you're kind of making the rest of us on-set feel a little inadequate. Right: 'take' 17!"). In any case, that "overlearning" wariness, so to speak, suggests that Mitzi Kapture has quite a facile mind.