Some comments about recent developments in cluing.
In the good old days, the indicator "key" was musical in nature, and implied a single letter between A and G. Now it is more often used to imply common three-letter combinations from the computer keyboard - ESC, TAB, ALT, DEL, CAP, etc.
Similarly, references to popular culture have become more frequent and varied. Some feel uncomfortable with this: however, the late great Araucaria had no such qualms, and was equally at home with classical literature and modern sports people. Two that appear frequently are ANT and DEC.