Originally posted by HadMatter:

Please tell me you have to physically roll. lol.

Heh, no, that would destroy everything in my room, including myself. :D
You have to flick down the right joystick, then press A on the same controller. Or crouch physically and press A. On the hand you just swinged for an attack. I quite nimble with my fingers, but that's just way too complicated to pull off. And it has no real advantage over simply moving backwards with the left joystick.