I have made only sporadic attempts (http://notionclubpapers.blogspot.com) to 'identify' the list of Notion Club members (listed on pages 159-160 of History of Middle Earth Volume 9: Sauron Defeated) with real life Inklings.
Indeed the striking thing about the fictional Notion Club is how un-like the Inklings they are: no dominant central C.S. Lewis character (no central character at all), lacking a Warnie Lewis character (military, benign, humble), and nobody with the peculiar character and impact of Charles Williams.
Nonetheless, sometimes I have tried to follow the associations in Tolkien's mind which may have led to the names and brief descriptions on the members page.
That is the fun of it: to 'get' an in-joke, and by such means to understand the workings of Tolkien's mind.
Thus, in the bath this evening, I recognized Notion Club member Abel Pitt as a play on real life Adam Fox: and (from Google) I discover that Jason Fisher has already made this connection.
The fictional biography of Pitt runs:
Dr Abel Pitt. Trinity. Born 1928. Formerly Chaplain of Trinity College; now Bishop of Buckingham. Scholar, occasional poet.
The obvious clue is that Pitt, like Fox, is an Anglican clergyman, both were scholars and occasional poets - but the real Fox was Dean of Divinity (at Lewis's college of Magdalen), a much more elevated position than Chaplain.
Abel is Adam's son in the Old Testament; but what link is there between Fox and Pitt?
My guess is that coal/ col links Pitt and Fox - a coal-pit is where coal is extracted while a colfox (a fox whose ears and tail are tipped with coal-black) appears in Chaucer's Nun's Priest's Tale.
The joke would presumably be that Adam Fox was best known for publishing a book length poem called Old King Coel.
If so, this is a tiny but interesting example of Tolkien's philological high spirits that he embedded such fancies in his story; and is illustrative of the characteristic scholarly foolery of the real life Inklings that Tolkien would expect them to get the joke.