This Rabbits Against Magic strip looked like a simple OY at first, but now I’m puzzled:
…
How does “tre” count as a pun on “trace“?
This Rhymes with Orange is an OY-Ewww:
Jack Applin submitted this Andertoons as a CIDU, asking “Is the one-eyed robot unable to see the traffic lights? [OR] Is is programmed to ignore them, giving an advantage to “driverless” cars?“
…
Mark Anderson’s original title for his comic #9221 reveals that Jack’s first question was right on the money: The gag is a reference to one of the most common anti-robot user verification tests, typically presented by the reCAPTCHA interface:
Later that same month (in 1967):
The punchline is in panel 5, but for many of us it would be a CIDU. The authors conveniently use panel 6 to make the joke clearer.
For more about the psychiatrist character, see https://www.washingtonpost.com/blogs/comic-riffs/post/barney-and-clyde-finds-inspiration-in-a-little-peanuts-farming/2011/07/20/gIQAcMmeTI_blog.html
Comics I Don't Understand 
For Rabbits Against Magic, he’s counting in Italian, not Spanish. Italian says tre, not tres.
@ Carl Fink (1) – I knew that it was Italian from “due” in the first panel, but I could not think of another English word (beside “trace”) that made sense in context of the second panel. Yes, he could have “disappeared without a tray“, but that would only make sense in a cafeteria. I still don’t know what the criminal pun was supposed to be.
Spanish would have produced a much better pun, and just by changing two words (since “uno” is the same in both languages).
I just realized, maybe that’s the point. The pun is not good because “tre” doesn’t sound much like “trace”, and that’s why he’s in the PUNitentiary.
The Andertoons robot can’t identify traffic lights. If it could, it would be able to solve CAPTCHAs. And we know robots can’t solve CAPTCHAs. The logical conclusion is that robots can’t identify traffic lights (or bicycles, crosswalks, etc.).
Whoops, scrolling back up I see you already caught on to the CAPTCHA answer. My eyes filtered out that bit because it looked a little like an inline ad. :P
To make it easier to find the arc, here’s a link to the Barney & Clyde strip shown at the end of the Washington Post article:
For those that think “tre” isn’t a suitable pun for “trace”, do you also not understand how punitentiary is a pun for penitentiary?
Today’s Thatababy Is a sort of self-meta OY …
Basil Fawlty: Manuel, there is entirely TOO MUCH butter ON THOSE TRAYS!
Manuel: No, Meester Fawlty. Not on dose trays. Uno, dos, tres.