The Steelers have been masters of disguise with their defense for years. It's an added bonus of playing a 3-4 defense, which has just three linemen on the field, often allowing the other seven players behind the linemen to shift around to different spots.
But that gets more difficult when you switch to a nickel or dime defense, something that is really now the base alignment for most teams. With just two true defensive linemen on the field paired with two outside linebackers as pass rushers, you're essentially playing a four-man front.
And when you don't blitz a lot -- as the Steelers did not do in last week's 23-16 win at Buffalo to open the season -- there's not much use in disguising blitzes that aren't coming.