We had one fail the knowledge test in my group. There was a complete mix of responses during lunch with regards to what people saw on the test. Some saw up to half of their total questions from the gouge. While some saw none. My recommendation to people is study study guide from Delta and understand the concepts. If you see questions from the gouge, consider yourself lucky. Otherwise be ready to know the answer because you understand the topic or can deduce it. AK said the purpose of the test is to find out who really wants the job. He knows that the material on this test was learned and forgotten a long time ago. It is also to see if you can self study, as that is required for training. Again, I recommend going to the source publications and reading up on each of the bullets from the delta study guide. It is dated 2007, so the material has not changed. Some will say that is a complete waste of time because every question they got was from the gouge. However, some will say it saved them because none of the questions they were from the gouge.