Yeah, I'm about 100% sure it's on the O Line.
If we're talking predictability, that's something to look at for the first pick-six. That dude knew that play was coming by alignment alone. I don't think I've ever seen a DB jump a route on another receiver quite like that.
To be fair, I'm fairly certain a very similar thing happened early in the 2008 Oklahoma game that was right up there with last week's game as first half meltdowns go.
But you're right. It's very rare. And very obvious.