If you consider that FEAST and DANCE are supposed to be "the same book" divided by POV, then you can see that the number of POVs suddenly doubled after STORM. No wonder the story suddenly became unmanageable for the author. If one divides ones story between twice as many different characters in twice as many different locations, then the story can only progress half as fast. And if your chapters contain twice as much bloat (as seems to have happened), the your story can only progress one quarter as fast.
And then the author starts repeating himself, perhaps because he fears you have not seen So-and-So in so long that you have forgotten what happened last time. More bloat.
A third aspect of the problem is this: In the first volume, not only were there only 9 povs, but they were mostly gathered in the same place and time and able to help a single storyline forward. GAME OF THRONES started most of the main POVs together, such that there were initially 2 main threads, which then divided into 3 main threads. Only at the end of the volume were the 7 surviving POVs completely scattered to the winds. Then did the author require 2 more (larger) volumes to complete the same level of plot progression that the first volume had. And yet many fans remained patient and even enthusiastic. Then it got worse ...
By the end of DANCE, we still have about 20 surviving POVs, and they are all still all scattered. One would think that the author would recognize this problem created by this vast scope, and adjust his writing style accordingly. But no. He thinks he has the time to describe how it feels for a character to urinate, and then describe a conversation he has with another character about how good he is is at urinating. Will his urinations skills have future plot relevance? He thinks he has the time to spend an entire paragraph describing a humble boat whose sole plot function is to transport a minor character from point A to point B (and leave him there), and then the author wastes another paragraph on how this minor character could have arrived on a nicer boat had things been different. George, you could have saved half a page, there. There are COUNTLESS such examples. Each chapter needs to have its length cut in half AT LEAST.
So where are we now? How close is he to finished.
THRONES was originally sold as the first of a "trilogy" (though the author admits he already knew better at publicaton). But his "trilogy" plan had originally been as follows:
Part 1: Game of Thrones: Covering War of 5 Kings.
Part 2: Dance of Dragons: Dany invades Westeros
Part 3: Winds of Winter
Well, he ended up needing a full 3 volumes to complete part 1. Part 2 was supposed to resume the story 5 years later, but for whatever reason, the author decided to scrap this plan and write an interim volume called "FEAST FOR CROWS". Let's call this Part 1.5. Well, as you recall, FEAST ended up becoming so bloated that it had to be split in two volumes, the second half being what is now being released as "A Dance with Dragons."
But the bad news is, this unplanned Part 1.5 is not even finished. All the threads that were set up in FEAST and DANCE to converge on Meereen have not reached there yet, as this latest closes. Hey, remember that guy Victarion with the dragon horn who set off for Meereen at the beginning of FEAST FOR CROWS. Well, he is still at sea. BUT HE'S GETTING CLOSE!!! When will Dany finally land in Westeros? At this rate, it won't be until volume 7, because she will need all of Volume 6 to resolve the impending climax in Meereen.