Originally Posted by Mantine
No, and that's not what I'm saying.
What breaks my suspension of disbelief is the sheer coincidental luck of many different things happening (or being revealed) all the right time, perfectly fitting for that exact situation... not the single individual things.
Try reading the meaning behind the words, rather than the words alone.
I've got to respect your persistence. But it is more than adequately explained by the comic itself. The key line is "You're too young to remember, but [Drow sign language] was quite the fad in its day." Drow sign language is a real D&D thing, not something Rich made up. It really was a fad back in the day (I confess to being old enough to remember), much like drow themselves.
Tarquin could have used any number of other ways to signal "let's get out of here." Tarquin chose drow sign language because it was showy and made him look cool. Rich chose drow sign language because it was funny.