Started late and endured a hiatus with this one, but found it thoroughly absorbing. Two of the thematic answers had to be worked out by back-formation, and getting the title helped immeasurably with some of the down clues, especially those towards the bottom. Some very devious cluing, and very few of the altered words in the downs were obvious. Can't find Ron in the list of setters, so either A N Other Setter under another assumed name or a fine début. A proper Listener, anyway.
One minor grump in the cluing for 26 - just a bit too "saucy" for my taste, and I'm not usually all that PC. Perhaps later editions of Chambers than mine have been more pejorative.