After reading the title but before reading the article, I was trying to imagine a situation in which anybody might want to fake surprise in a work environment. The only thing I came up with was as a teaching mechanism, as in: "your program is crashing when you divide by zero instead of returning NaN? How strange! Let's investigate together".

I was quite surprised to see that by "feigned surprise", the article actually meant something along the lines of "really, you expected an integer operation to return NaN?". The article does explain why people might say that, but I still have a hard time believing it. Why would anybody want to say that? It's not helpful at all.

I guess I must be lucky never to have worked in the bad working environments described by the article.