Q:

Did Heller base his sarcastic swipe at academia on any actual example?

In chapter 1 of Catch 22, Yossarian describes how he makes a boring task (censoring letters) interesting by erecting "dynamic intralinear tensions":

All the officer patients in the ward were forced to censor letters written by all the enlisted-men patients, who were kept in residence in wards of their own. It was a monotonous job, and Yossarian was disappointed to learn that the lives of enlisted men were only slightly more interesting than the lives of officers. After the first day he had no curiosity at all. To break the monotony he invented games. Death to all modifiers, he declared one day, and out of every letter that passed through his hands went every adverb and every adjective. The next day he made war on articles. He reached a much higher plane of creativity the following day when he blacked out everything in the letters but a, an and the. That erected more dynamic intralinear tensions, he felt, and in just about every case left a message far more universal. Soon he was proscribing parts of salutations and signatures and leaving the text untouched. One time he blacked out all but the salutation "Dear Mary" from a letter, and at the bottom he wrote, "I yearn for you tragically A. T. Tappman, Chaplain, U.S. Army." A. T. Tappman was the group chaplain's name.

Was Heller having a go at a particular pompous academic or clique? Or, did he invent this strained term?

A:

Unless I'm missing something, after sifting through Google for awhile I haven't been able to discover any other usages of the term other than in the book. Even searches of Google Scholar and various academic journals and databases don't show any results (other than in articles about - or explicitly referring to - Catch-22). That being said, I haven't been able to find evidence of any usage of the term prior to the book (or any actual usage of the term in academia), and all references to it appear to be in the book itself or in discussions of the book.
It's quite possible that the author did have a particularly pompous academic in mind. He studied English as an undergraduate at University of Southern California and New York University and then earned a MA in English from Columbia University in 1949 (approximately 12 years prior to publishing Catch-22). He then spent a year as a Fulbright Scholar at Oxford University and taught composition for 2 years at Pennsylvania State University. (He later taught again part-time in the 1970s at Yale University and University of Pennsylvania, but that was after the publication of Catch-22).
My point in mentioning that is that he doubtless came into contact with many academics in English in his time at 5 different university English departments (at least some of which would've presumably been pompous). Maybe he did have someone specific in mind, or maybe he was poking fun at several of the pompous academics he had known, or maybe this is just an aggregate.
Given that he seemed to have invented the term for the book, it's more likely that he was poking fun at academia in general rather than any specific group or individual; while he may have had someone in particular in mind at the time, that doesn't seem to make its way into the book specifically, and he presumably would've known quite a few people he could've based that on.

