Probably because it was too good an answer. I will have to remember that one. 
It works a little better with “non-objects” entirely, like the cresting of a wave as it hits the beach, or the illusion of motion in moire pattern interference fringes. You can (theoretically) have a wave that hits the beach so very close to perfectly parallel, that observers (in an inertial frame of reference) would witness the event simultaneously, at any given distance apart, so the event appears to move faster than light.
It doesn’t really; it just appears to. The wave-crest events aren’t “objects.”
You and I, using atomic clocks, could agree, ahead of time, to utter the same word – “Algonquin!” – at very close to exactly the same instant. To someone observing, it might seem as if we had sent a signal back and forth FTL. Really, we didn’t. No actual signal travelled. We brought the information with us, at ordinary speeds of travel.
I would say he’s right. Darkness is absence of light so darkness have no moving parts. It just exists.
I remembered last night while trying to fall asleep that the program was “Says You” rather than “Wait Wait Don’t Tell Me.” Just want to set the record straight.
Actually: "“Light thinks it travels faster than anything but it is wrong. No matter how fast light travels, it finds the darkness has always got there first, and is waiting for it.”
Do you mean Betelgeuse and Rigel? If so, the distance is actually 324 light-years (plus or minus a hundred light-years or so), according to this distance calculator.
Two quotes, both from Discworld.
**
"Light thinks it travels faster than anything but it is wrong. No matter how fast light travels, it finds the darkness has always got there first, and is waiting for it.”**
and
"As yet unmeasured, but believed to be faster than light owing to its ability to move so quickly out of light’s way."
Sorry. Couldn’t resist.