The author just keeps on loading more and more people in this brilliant work that he started and now after the completion of trilogy the history work continues. The history is not written in that old boring style in which usually histories are written. It is in form of incidents written in a story like pattern, the listener can feel the continuity in it all the way.
One House and then the other, the legends attached to them and the ancestors that laid the bases of the thrones come one by one. The history is told along with the stories about the legends that are awesome, then these stories associate to legends that have been our favorite in A Clash of Kings. Not much war stuff but the reasons behind the war and the causes of fights and truce that took place hundreds of years before the real heroes we talk about. The World of Ice & Fire the book goes as far as building a family tree for the Houses. There are some weaknesses at certain point the book appears to be losing the fantasy side in most chapters and is like the boring literature.
Then one dragon glide or scene of a battle takes the boredom away with the wind. It was because of these issues that George R.R. Martin now has started taking help from other masters of the field like Robin Hobb and Garth Nix. The variety was lacking, more brainstorming was needed and thus the author assembled a team. In narration even there are multiple voices now, Arthur Morey, Kirby Heyborne, Ralph Lister, Elliott Hill and narrators like John Lee put the spice of variety in the series that was appearing to look a little dull.