I'm reading Ivanhoe right now and very much enjoying it. Each chapter in Ivanhoe has an epigraph, often very closely related to the plot of the chapter, meaning that it is often very easy to surmise exactly what will occur purely by reading the epigraphs. While a lot of Ivanhoe is fairly obvious - I pretty much saw who the Black Sluggard and the Disinherited Knight were immediately - this strikes me as very odd, to give away the plot in such a significant way.
Some of the epigraphs are more commentary on what is occurring, which makes me wonder - why did Scott not include more of these "commentary epigraphs" and less of the "plot epigraphs"?