After a lot of slow chipping away at the blank grid, I finished the Listener puzzle tonight. I broke into the puzzle at last when I got four answers from Set 3, which was just enough answers to enable me to hypothesize that, unless there’d been a fluke and the answers were all across or all down, there was only one way to fit them into a quadrant with valid crossings. That hypothesis turned out to be the right one, and from there I was able to complete the quadrant. I finished the rest of the puzzle one quadrant at a time, too, and put the last letter into the grid just as the house lights were going down a few minutes after eight for the evening of ten-minute plays Dave and I were in the audience for.
Speaking of which, we were pleased to find that our friend Martha had written what was easily the best-crafted playlet of the evening, one of the two best in both Dave’s and my opinion. And fortunately not the one containing the line that really set my editorial teeth on edge. No, no, no, the name Zoë does not have an umlaut, it has a diaeresis. A certain naïve writer may want to coöperate in some preëmptive reëducation.
Scratchings 
It’s what comes of using what appears to be the same symbol (or in this instance diacritical mark) in two different systems (although in German the umlaut only goes over a, o, and u, so diaresis is usually everything else, but ‘coöperate’ crosses the streams. As it were. And we will not get into heavy metal band names); just as one must be careful, when discussing factorials in math prose, not to exclaim.