Very good point.
In the case of the test I was asked to take, reportedly to test my understanding of C++, it had practically no C++ in it, but rather plain old C. There were only two people in the company (yet another startup), and my gut feeling was that the young software fellow was the one who wrote the test, and the questions sure looked a lot like something you might get in a test in a high school or college programming course, just to make sure you remember the particular details of what was taught during the prior week. It was not at all a well thought out test and I can't imagine how they could deduce anything from it as far as my overall development and design skills.
Also, as far as tests being used to weed out the bad programmers from the good programmers (generally by the HR departmet) so that the real decisin makers dont have to waste time actually interviewing people who clearly won't make the cut, I'd have to ask: "How many programmers can there actually be here in Hawaii?" If every single one of them showed up for an interview, how much time would it actually take to go through them and find the perfect match for the company? :)
And one last thought: If anyone actually does know of a company looking for an experienced (thirty five years!) C++, MFC, application development software engineer who really enjoys the GUI part of a project, let me know !