Dan Brown cheats.
I recently finished the draft of a novel I am writing that used multiple points of view like Brown does. I realized I was going to have to throw out a bunch of material I wrote from one character’s point of view just because he KNEW TOO MUCH. Being in his head would have given the mystery away. Better to have him not be a point of view character in the book and remain enigmatic, then to let the reader into his point of view and have him somehow just not think things that would give the game away.
Because people? Don’t control their thoughts. We think what we think.
This is how Dan Brown cheats. In both this book, and The Lost Symbol, he wants to have a big twist at the end where a character or characters are revealed to be more than we thought they were. And he does this by taking us into their heads and just not showing them thinking of things that are no doubt on their minds, like, “How am I going to pull blah-blah-blah off without giving myself away?” That would really be foremost in their minds, I would think.
Sometimes, he has characters think of events in their lives that are later revealed to never to have happened. Were they rehearsing their fake backstories to help pull off the con?
In retrospect, you can see the clues Brown scatters for you throughout the book that reveal the twist, which a twisty story should do, but you also see the cheating attempts at misdirection.
Still, I read Dan Brown because his books are fun. They’re scavenger hunts where the treasures are a copious quantity of well-research archeology and history. But great literature, this is not.