Before I get to explaining how to read a royalty statement (which I keep putting off because, let's face it, it's not the most interesting topic to write about) I thought you might be interested in hearing this interview with James Patterson that I heard on NPR last night, where he describes his writing process. Since the process seems to involve more editing than actual writing, I'm changing my answer to Harper Lee.
That said, Patterson has a point. Artists have been taking their concepts and hiring them out to others to execute for years. Take Jeff Koons, for example. Patterson argues that people have a hard time accepting when a writer does this (though they shouldn't because it happens all the time, whether readers are aware of it or not).
We could argue all day whether Patterson and Koons are producing real art or pure product, whether there is a difference between hiring someone to craft a sculpture or a paperback, whether you can truly call yourself the creator of a piece of art if you have a hand only in the concept but not the execution. I will say, however, that when you choose to skip the actual process, something is lost in both the art and the artist.