Prof. Kramer postulates that the people themselves hold the right to judicial review and recognizing what is and is not Constitutional.
Like math and science Americans have been trained to view the law and especially the Constitution as the sole purview of lawyers and intellectuals.
(BTW I don't agree with Kramer across the board)
The Founder's masterpiece was written in plain English to be understood by ordinary citizens. It was not written in arcane legalese, so that it would need be interpreted by oracles.