Yeah the author glossed over this a bit in my opinion. In infinite precision math you're correct, but at some point the signal in those higher frequencies is going to be reduced below the precision of the storage data type, never mind the dynamic range of the monitor and camera he's using.
It seems clear the author does not have knowledge on the subject, more than glossing over -- the article even emphasises that information is removed by the blur (100% wrong). I agree it may not have destroyed the experiment entirely, but it does mean the experiment was conducted without knowledge of basic signal processing and I would prefer a more through study or analysis before drawing conclusions...
