I had my CVSA this passed week and I passed!  Anyway, it was pretty textbook.  At first he went on to say that he was like a "priest" and that I could tell him anything that I did not tell my background investigator.  If I gave him any admissions, he would not hold it against me since I would be telling him the truth.....ya right.  So, I made sure that I did not make any admissions (I have nothing to lie about, seriously).  Anyway, after he read me the questions, he hooked me up to the .50 cent mic and started the test.  There were about 7 "significant questions" and 20 "useless questions".  He told me that I was having problems with one question....."do I accosiate with any known felons".  Funning thing is that I don't even know a felon, let alone have one as a friend.  Wow, what science this is.  Anyway, we re-worded the question and I "passed"  After the test he showed me how the software worked and such.  Pretty much what he said was that after he asks a "significant question" there is a "useless question"  Anyway, if the "useless question" still shows the "block" type waves, that would mean you are showing deception.  So, pretty much what he told me was that on a "significant question" you can have a "block" type wave reading, but on the "useless question" after the "significant question" it should be back to the normal non-stresses peak-type wave.  I guess the theory is that a "liar" will still be thinking about the "lie" after the question is already finished.  So, after the test he got a "cold call" and everything was OK.  Overall, this whole thing is BS.  The only advice I have is that you remain as calm as possible.  It seems that the more you dont care and daydream about things you are going to do over the weekend, the better.  Good luck and I hope this helps!!