Obviously, my test is complete and utter tripe too. Interestingly, Forer's evaluation was taken strait from an astrology collumn. Obviously, people of all astrological signs have taken that test with no significant difference in results. You should be able to see what this says about the accuracy of that type of test.

So, how does it work?
The same way astrolgy, psychics, and all other manner of things do, of course! It's a little trick called cold reading (Read about it at the skeptic's dictionary), which involves general statements being said and you picking out what seems to fit the best subconsciously.