At this point, I'm partially convinced that Karras' snaps were on purpose. BB saw something on tape and said "Pittsburgh likes to jam the receivers and by snapping it slower, they get a quarter second more time to come off the line before Tom is ready to throw..." or "Our offensive line is faster off the ball than the Steelers, and a slower snap helps them set up quicker..." I have no idea, but to hear Tom Brady say the snaps were fine, when everyone in the stadium (and I'm sure everyone at home) was looking at the snaps and going "WTF?" leads me to believe that perhaps, the Pats found yet another tiny edge they figured out a way to exploit.
Either that, or he's covering for Karras, which is entirely possible, but I have a hard time believing they cut what's his name after 2 days when he had started like 74 consecutive games and nobody thought it would be important to work on Karras' snaps before last night. I wouldn't be surprised next week to see the snaps come back at normal speed and everyone just goes, "Yeah, we worked on changing it up.."
Or maybe they are REALLY trying to protect Tom, and don't even want him to potentially jam a finger.