so someone who wears glasses and a pocket protector has nothing to do with geek magic?
No. Way back before geek came to mean what you commonly hear in high school, it was a term applied to circus freaks. The term referred to someone who would chase a chicken around only to bite the head off, who acted as sort of an opener for other freaks. However, it has come to also include also sorts of circus sideshow beings - Siamese twins, the human blockhead, sword swallower, etc., they could all be called Geeks.
As such, Geek magic tends to be grotesque, gory, and bizarre. Saw and Thread are examples. The right presentation can make Wounded or even Control an example of Geek magic.