Yes, I do think you would have more luck SRing and dipping for specific questions. For an essay you will want to show that you have some sort of understanding or made an assessment of the topic. The purpose of being able to answer the unknown (at this time) essay questions is still the purpose. However in order to fulfil this purpose you'll want an understanding of the text at another level.
In other words keep your orginal purpose and add specific questions that helps you consciously expand the information in the text to help you meet that purpose.
Alex
