Mhmmm... I remember doing half of everything so that I at least had a vague idea of the subject.... It usually worked just fine for me because I'm good at making shit up as I go (one memorable time, I had to read "crime and punishment" for school and the day of the oral test I had read just about 20 pages. The prof called my name and asked "Nastasia, are you ready for the oral test?" and I was all "Sure, Prof!" and then started rambling about the authour and that my favourite part was the beginning (ahahah) of the book because it was really intense and set the bar for the rest of the story and then slipped into a disquisition about the word-building and parsing and construe and I got an A without having read a single chapter. It was pretty epic)
BTW, what book are you reading?