And I'm wrong; what we do have is Elly being martyred because John quietly laughs at a crack-pot theory of hers.
Panel 1: We start off with Elly reaching into the dryer.
Panel 2: As she holds a sock in her hand, she thought-bubbles "It's happened again"; whatever's happened has made her react by staring the Bug-Eyed Glare of Existential Horror.
Panel 3: She continues to be goggle-eyed as she tells John that every time she does the laundry, she winds up with unmatched socks.
Panel 4: She's decided there can only be one explanation for this phenomenon.
Panel 5: Elly's decided that the speed of the dryer and the forced, heated air send them into another time dimension.
Panel 6: John stares at Elly as if she had a third eye as she declares that in the year 2050, whoever's living in the Pattermanse is suddenly going to acquire a bunch of odd socks. I don't blame him for being freaked; rather than admit that there are simpler explanations (like people not actually putting both socks in the hamper, the sock in question falling between or behind the washer and dryer or actually ending up inside a garment), Elly has turned into Agent Mulder.
Panel 7: Suddenly remembering the simpler explanations, John laughs politely as he walks away from Elly as she yells that he has to admit that it's possible. Actually, Elly, he doesn't HAVE to admit sweet dick-all.
Panel 8: The end result of John's disturbing lack of faith is that Elly thought-bubbles that the trouble with most brilliant theories is that nobody believes them.
Summary: The conclusion that Lynn wants us to draw is that John is an evil, bone-head dork who's incapable of taking Elly seriously; too bad for her that Elly isn't actually capable of being taken seriously. She's instead depicted as the Very Model of The Modern Blithering Idiot.