If Irvin is out there getting sacks, then that's a good sign the Pats no huddle offense has been abandoned/isn't working. Because once they see Irvin on the field their going to their no huddle and going to start running the ball. Since Irvin only comes in on passing downs, the Pats are likely to be trying to throw for a first down on the play he comes in. A sack then stops them cold. They convert, however, and he may not get off the field for a while and they may not throw a whole lot of passes during that time.
Richard Sherman doesn't just wanna get in your head, he wants to build a vacation home there.
R. Sherman: "I don't want to be an island. I want to be a tourist attraction. You come, I take your money & you go."