Why?...
Why are physics TAs sadists? They've done the "Who are you, what's your name/major" shpiel and know that no one in the room are physics majors. You're preaching to a room full of engineers and you're all "theoretical physics" this and "cylindrical coordinates" that. CS TAs just reinforce the material; they don't reteach CS 101 in PERL. So why are Physics TAs evil?