The tricky thing is, as clever as this conversation is - and it is, especially the final line - even if it happened in real life exactly as we see it in the comic, it'll never be funny as a comic. Because readers (critical ones, that is) will see it and think "that's all well and good for characters, but they aren't acting like real people, they're acting like scripted characters." It's the reason I hate most of the alleged comedy in Shakespeare: It's all so layered and complicated that I stop hearing characters and just hear a writer, trying too hard.
And another thing: Is it just me, or is this another comic in quick succession that deals with distinctly pre-middle school academic material? Last time was basic multiplication tables, this time it's similes and metaphors, a distinction I vaguely recall a seventh grade teacher attempting to teach me.
How can you even be "bad at metaphors," the way the woman in panel 2 claims? How does that make sense?