Even most physicists don't understand Feynman's point that QM is called "mechanics" for a reason: it's a set of mechanical rules for getting the right answer. It tells you nothing about how the universe operates behind the scenes so as to produce the same answer as QM. Feynman's little easy-to-understand book on QED should be read by everyone who thinks that QM is more than a tool for performing calculations. (And read Tegmark's book for an example of what happens when an intelligent person reads meaning into QM.)
Regarding the actual article: at first sight, this looks like a great experimental verification of something that no one (as far as I know) doubted; but it's always good to confirm another prediction of QM that appears bizarre to us.