I've had the same thought, that GRRM might have changed his storyline just to throw off fans who have doped out too much for his liking. The superabundance of characters gives him plenty of options. He writes long, so there is plenty of time in the book version to develop a minor character into a new lead. In the tv version, not so much. They are simplifying as they go.
I wonder if GRRM will burn all his notes when he's done, or let fans see the evolution of the plot over time.