The best job I ever had, 2.5 years working on the ASTRAEA civilian UAV research program for Cobham in UK, I failed the tech test 3 times, but they employed me anyway because they knew the test was a pile of tosh. My own impression of the test is that it was a test of imprintability. Most standard jobs, employers want impintability, because it normally results in quick learning, enough to do repetitive work most efficiently, but not great for investigative roles requiring innovation or curiosity - They knew me well enough from other roles earlier, to know I fitted the research role. In hindsight I probably had to fail it, to meet their expectations, and thus get the role :)