Probably this occurred to me because I was finishing up an edit, which means I was also finishing up the style sheet, the document that serves as a guide to my edits on a manuscript. The style sheet is where you list the characters and proper names and other notable words and terms that occur in the text, and where you mention any rules you enforced that contradict the standard style guides, The Chicago Manual of Style and Words into Type. If you feel fancy, as I generally do, you can include descriptions of the main characters, just so everyone who reads the manuscript after you can confirm at a glance that someone described on page 187 as having blue eyes is supposed to have blue eyes. In compiling the style sheet you have to decide about stuff like are you going to enforce the each other/one another distinction. I think that distinction is pointless, so I never actually mention it on the style sheet, but the style sheet is probably what got me thinking about it. I'm pleased with this comic because it doesn't have a conventional punch line and because it's a fairly accurate depiction of how copy editors argue about stuff like this. Mostly without the physical assault. I also like the variety of poses I used here -- as you have probably noticed, mostly I draw people standing facing each other (and flailing, occasionally).
Also accurate is that both of the copy editors depicted here are women. In my experience women outnumber men in my profession by probably three to one.