I also did thousands of test questions. I though it should be easy to pass this exam, but when I was answering the questions during the exam, it surprised me, because of more than 90 percent of questions I never seen before. I just answered the questions by my feeling, not totally sure the answers.
First of all let me say congratulations on your success in passing the exam. There are many individuals I fear that have the same experience as you described. Reading all of those books should not only allow one to learn new concepts; it should allow one to reinforce knowledge they already have gained by actually working in many of those domains. The exam as I was told is not to just read the books and answer some pretest exam quiz questions; it is to test ones knowledge of concepts and understanding. Individuals who do allot of pretest exam quizzes and consistently score high "should" do well. However, they will only do well on the actual exam if they can discern what the questions are actually asking them. Some of my co-workers said that once they started the exam and saw the actual questions on the exam had a brain meltdown as none of those questions were recognizable, and they had no idea what the questions were actually asking them. I work in an enterprise environment and constantly tell my co-workers that I am old enough to know just how ignorant I really am. Meaning, I constantly read through books and whitepapers look things up on the internet and save all kinds of documents. When I passed the CISSP exam I had put so much time into it that I actually figured out I had no life other than the exam. A few tested after I showed my pass result figuring that if I passed it must be possible for them to pass as well. After very little effort and time spent on preparing for the exam, they came back to me and asked if they could use my materials to study. Days later they came back and asked how long it took me to type up my own information in condensed version format; Answer: I wasn't concerned how long it took as long as I passed. I also told them that looking at minimum passing score was a joke. Take every quiz or exam to ace it, and if they fall short, so what, they should still score high enough to pass. I now have several individuals who understand me when I say "I am old enough to know just how ignorant I really am." Again, I would like to send praise to you for doing what many have not or cannot and that is pass the CISSP exam. Congratulations and may your journey carry you far and grant you nothing but success.