23 september answer

3). Is Drucker stating that since Instructive language is to protect us and prevent us from making a mistake that maybe someone created before, but is holding us back from exploring or making our own decisions? [Kai]

I think perhaps she suggests that we need to at times take a step back from the language and images that instruct our everyday lives and look at them more critically. However, our acceptance of these image/word combinations and their symbolic meanings is essential to the cohesiveness of our current society. This is why images such as this one are so effective; they draw us out of the given meaning we assume of the image. Drucker perhaps wants us to question the medium if not the meaning.
I also think this might be the reason it's so common to steal instructional signs. In countless dorm rooms, apartments, and garages I have seen NO _________ signs (or, among my obviously classier acquaintances, SPEED HUMP). The transgression is not only disobeying the signs, but taking the sign themselves- and therefore eliminating the message and its context. Eliminating the context begins to wear away at the legitimacy of the meaning, making it funny instead of law; it eliminates that location indexing that Drucker references.