"Predatory" reading makes me think of building a house. You have to get the foundation (argument?), build the frame (topic sentences and "signposts"), and add the walls, roof, ect. (the rest of the written work). After you've built your house, you should inspect it (reread) to prepare for sale.

A good signpost should let us know where we are going and help us find our place when rereading.

"Argument"-this is our main target.

Ask your "why?" (Why does this matter? Why was this included?) and your "What?" (What is the writer's goal? What is the main take away here?)

Reading for pleasure gives us the time to take the material in as thoroughly as we'd like. "Predatory" reading of scholarly works requires us to select our target and take firm hold of it.