I don't think that an author has much power to control how people read his/her works. After all, once you've experienced something you can't go back and "edit" the way you reacted just because someone tells you you're wrong. I've had people react to my work -- writing, dancing, etc -- in a variety of different ways, and sometimes they've seen things that I didn't consciously mean to do, but that I would have if I had thought of it.
That doesn't mean that every interpretation is equally valid, of course. Interpreting "Teletubbies" as an attempt to further the gay agenda would be a good example of a reader who is so obsessed with his own issues that he can't see the text (or its context) itself, only the beliefs he projects onto it.