"What if" math joke: the derivative of $\ln(x)^e$ Randall Munroe, the creator of xkcd in his latest book What if writes (p. 175) that the mathematical analog of the phrase "knock me over with a feather" is seeing the expression $ \ln( x )^{e}$. And he writes regarding this expression: "it's not that, taken literally, it doesn't make sense - it's that you can't imagine a situation where this would apply."
In the footer (same page) he also states that "if you want to be mean to first year calculus students, you can ask them to take the derivative of $ \ln( x )^{e}$. It looks like it should be "$1$" or something but it's not."
I don't get the joke. I think I am not understanding something correctly and I'm not appreciating the irony. Any help?

Good Lord of Purple Unicorns; I got the book a day ago, and I'm on page 172. XD 
He means to say that many expressions like $e^{\ln(x)}$ and $\ln(e^x)$ equal $x$, but if you want to be mean to first year calculus students (owing to their naivety), they'll initially think it's a simple problem, but in fact the derivative of the expression $\ln( x )^{e}dx$ is 
$$ \frac{e(\ln(x))^{e-1}}{x}$$
