If two characters are thrashing arguments back and forth about whether democracy is a sane form of government, the arguments will arise as they occur to the characters, not in an orderly fashion like a textbook. Indeed, if it resembles it too much, the readers may reject it as too neat and schematic.
And there may not be a good order to put them in. Some arguments are better in sequence than in structure.
Plus, of course, the way you've still got to build complications to climax, and keep a sequence of cause-and-effect going to drive the story. Just because you're deriving it from an abstract argument doesn't let you off on any story requirements.
