That's the idea of activation you start where your instinct guides you with be the major core insight. If you ask what is the plot you probably have to superread a few sections to pin it all together... but you concentrate on looking for that. Even if you superread the book from cover to cover in 20 to 30 minutes you allow yourself to be prompted to pause for the plot or charactor or theme that you are seeking. The rest you just wiz over. (Reserving it for the rapid read.)
Alex