Educational: Marketing propaganda - Coin Grading Test FAIL - Tested...but no correct answers exist!

CoInWeek editor takes the PCGS Grading Challenge. Put on your thinking caps folks! He is graded on how many out of 10 slabs he guesses the "right" grade on. Yet cracking and re-submitting the coins, they are never guaranteed the same grade again b/c nothing scientifically verifiable is used to grade coins! How can you say call something a "right" grade when the "right" grade can change? The companies tell you their grading is subjective, yet hope you do not think about that fact when they call a grade "right" or "wrong!"