Here’s the telling paragraph:
In short, I despair of our supposed plans for toppling the New Deal. And in truth, there is no Constitution in Exile movement. Google the phrase, run it through Lexis-Nexis, search far and wide: No conservative or libertarian activist, theorist, or judge has used the term since its casual mention in 1995 (and few have ever heard of it).
This helps explain my shock as a dues-paying, secret meeting having, long term member of the Vast Right Wing Conspiracy at having never heard the term until it was brought up quite recently by a left-leaning commenter.