Well, it's definitely what James Patterson does. He has an entire stable of ghostwriters, although I don't think they're his editors. I'm not even sure if the plot ideas are all his either or if he just puts his name on the novels to make them sell better. But yes, I'm pretty sure GRRM slaves over every single word himself. He seems like too much of a perfectionist to trust his words to anyone else, although he could probably speed up his pace of writing by not taking on so many editing projects and the like~
