I can only speak for what I've seen this season, but the blitzes seem to be at the right times and would have gotten home, had the back end (Williams) done what he was supposed to do.
Whatever adjustments they made with the safeties has been the difference, that and Latt playing up to his potential.
From what I can tell, we went from playing cover 2 to playing cover 3, single deep safety (williams).