1) In a 4-3 base, the blitzing of a single linebacker can lead to confusion in opponents' blocking assignments. If the LB is well adept as a blitzer, it can really add a lot. However, you cannot blitz the same LB (or same position) consistently and expect good results. In most cases the biggest advantage gained is in the confusion created, that is lost if the same player blitzes every time.
-From the huge defensive AI sticky thread.
It talks about confusion when it comes to blitzing assignments because i have seen it on film and I wanted to know if changing the style of pass rush has any effect