Besides, nobody thinks book five will be about Slaying The Dragon -- although the dragon will wind up dead, I'm sure. The series is called "The Dagger and the Coin" because it's about armies and banks. That's what "realistically gritty fantasy" means, right?
No, what really starts to fall apart is Basrahip's religion. Here's one last fantasy trope for the series to deconstruct: the crusading Church Militant of single-minded cardboard priests, led in perfect unison by an insane but tactically brilliant vizier... No. Why would you ever expect that? Churches schism over the color of the drapes. The nature of the spider-priests means that when they were one monastery-full hiding away in the mountains, they were all on the same page, and Basrahip was just the most charismatic of them. But now Basrahip is in the capital and there are temples dotted all over the continent, which means -- remember the game-of-Telephone? -- there's linguistic drift.
Also, think about it. Basrahip is incapable of doubt. That means he's insane, maybe tactically brilliant, but strategically -- an idiot. A blind idiot. He can't be anything else. That becomes very clear to the reader, although not, so far, to Geder Palliako.
Arrayed against him is a dragon (good luck with that), various free cities (so far Geder's armies remain unstoppable), and our heroes. Our heroes continue to quietly travel the world, looking for ways to array better. Okay, Cithrin -- as a prominent bank official and Geder's well-known secret crush -- is travelling not-so-quietly.
Clara Kalliam meets up with other significant Kalliams. Marcus Wester meets up with Yardem Hane and doesn't bother to kill him. Master Kit sits back and argues philosophy. (I like the guy but he doesn't have much plot power at this point.) And Cithrin, ah, Cithrin pulls the banking plot thread which has been patiently waiting these past four books. I am very, very happy with Cithrin's story.
Yeah, I'm happy with this entire series. You can probably tell.