Actually you're more on the right track than you realise. The first book probably needs another 30 to 60 minutes to gel fully for you and that would put you way over the top on regular readers that still have 4 or 5 hours of reading to do and had no idea what they wanted out of the book.
When I get stuck and am not pulling information from the book and activation isn't leading me to anything. I take a moment to reflect back on my purpose. What was it I wanted or needed to know from this book and for what reason. This causes me to review what my question. If I know that I have to know something out of a book but am not forming questions and trigger words are not helping I look back to the content and index to see what raises my curiosity. Sometimes I notice something odd when I do that. One of my tricks is to turn the heading and subheadings into questions. If I can answer the question then I already know the material. One of my reasons for superreading and dipping seeming not to be working. The other thing I found is that the answer is quick and easy to find, its usally somewhere under that heading. In which case I often prefer skittering. I might zig zag up and down the page to connect with the sentence or paragraph that 'clears' up the answer for me.
My metaphors, I hunt for them, like a dog digging for a tree root. 
Alex
