Either by accident or design, this grid is exceptionally difficult to break into. I have never had so much trouble piecing things together after 75% of the clues solved. The last few carte blanch puzzles I've broken into quite early.
I worked out very early in the game that the twelve-letter answers and the two eight-letter across answers could not intersect. As far as I can see, the two eight-letter down answers do not intersect with the pairs of five-letter across answers that S_Pugh has said intersect with the long down answers. All this means that the normal entry route into a carte blanche via the longer answers is denied to solvers.
Given the number of hours I have spent on idly moving answers around on a grid, I passed the 'no longer enjoyable stage' long ago. It's pretty clear from here and the other site that few people have made much progress. I suspect this has been put out to reduce the number of all-corrects. I'm it will succeed in that. The setter has made very few concessions to the solver - a carte blanche that's hard to break into, one with an unclued entry of unknown length, some fiendishly difficult misprints (anywhere in the clue) and some very indirect definitions.
Even Sabre makes concessions to solvers in his toughest puzzles, and I have usually got a lot further with a Sabre puzzle by this time on Sunday. Challenging puzzles can still be enjoyable, but this one is bottom of the list for enjoyment.