As far as we know, Mark Twain is/was not a member of the PPC.
Twain introduces Cooper's offenses by suggesting there are nineteen rules governing literary art in the domain of romantic fiction, and that Cooper has broken eighteen of them in his novel, The Deerslayer. Below is a summary (and re-ordering) of these offenses that does not capture Twain's sharp pen (nor is it trying to). For the witty exposé, one should read the original.
- Stories require a plot.
- Scenes should further the plot.
- Characters shall not be cardboard cut-outs, but have depth.
- Characters need an excuse to be in the story.
- Dialogue should be natural, flowing, and have a purpose.
- Characters should behave in character (what the author shows of the character should match with what he tells about them).
- Characters' speech must be consistent.
- Characters behaving stupidly must not get away with it.
- Magical occurrences in a story should still be properly explained.
- The author must write the characters so that the readers feel the same way about them as the author does.
- Characters' behavior/actions should be predictable based on their characterization.
- The writing should be clear and unambiguous.
- The author should use the right words (avoid malapropisms).
- The author should not include unnecessary details.
- Nor should the author leave out important details.
- The form should be neat.
- The grammar should be good.
- The style should be simple and straightforward (no purple prose).