The best part of this is the movement created at the snap from defensive end Stephon Tuitt. He gets the center to over-commit to Tuitt's outside shoulder, giving him an opening to swim past him into the A gap. Because Tuitt gets so far over with the center, the play's real intention is revealed in bringing Worilds over Tuitt's spot, thus forcing a guard to try to race over two strides to contain the much faster No. 93.
Smith is locked onto his receiver and has a chance at a play downfield. He sees cornerback Brice McCain coming at him from the back side of the Steelers' blitz, and knows he has two receivers down the field in single coverage.
It's too late, however. Worilds is going to land just after Smith throws the ball, forcing the incompletion.
It's a well-designed blitz that highlights the benefits and risks of the concept. A smart quarterback like Smith can see it coming as it's developing and knows where he needs to get the ball. At the same time, the confusion caused by Tuitt's initial movement creates a situation in which three Chiefs' blockers are unable to contain two Steelers' rushers because of a coordinated attack into areas they can't protect with the angles they've been forced to take.
This is why we love Stephon Tuitt, though. It's his quickness off of the ball. He starts on the outside shoulder of the center on the offensive right side, and ends up head over the left guard. In doing that, he stretched the protection scheme wide enough to force the right guard to come two gaps over to take a stunting Worilds.