Brock just actually proves it WAS play calling, at least in that particular instance. Two things could've happened: either Wilson could've audibled out of that play call and didn't, or Bevell just got outguessed. Let me explain.
Look at the chalk talk. See how Percy is lined up in the slot ? We have one Nickle CB splitting two WRs in Kearse and Harvin. But how can one guy cover 2 WRs Drew? You might ask. Answer: you don't. The FS is actually going to be responsible for Harvin. But he's in single high and shaded to Lynch's side just a bit. So the next question would be: why would you trust a FS playing 15 yards off of a WR of Harvin's speed to cover said WR and give up literally half the field to do so? How would you cover a guy that can go up the seam, then cut to the outside and literally have no one there to top him ?
Ding ! Ding ! Ding ! That's the million dollar question. The answer ? Dallas KNEW Harvin wasn't going to go deep. They KNEW it was a screen pass. That's the only way you can cover Harvin in that situation. There is absolutely no way that FS can cover Harvin if he goes up field and then fades to an out route. That FS might not be able to cover Harvin if he just flies straight upfield (keeping in mind most Safeties aren't as fast as CB's).
Well, the Nickle could split off and cover Harvin if he goes upfield. Sure, then who covers Kearse ? He's got an easy 10-12 yard reception with only a FS coming at him from 15 yards away, or a CB coming off of his guy to make a play. This is a gamble by the Cowboys and it paid off in spades because we're so damned predictable.
Brock Huard is right. They invited that screen. We had numbers: 3 WRs to 2 CBs. Problem is, there is two ways to take advantage of that, and we played the one way it could work out in Dallas' favor. The ONLY way Dallas wins that play is if one of their guys beats a single block.
If I'm a coach or QB and I see that, I'm sending Harvin. Wilson throws that ball to Harvin's left shoulder and draws him away from the FS.....and there is literally no way they can stop that, short of a poor pass or a drop on our part. We're just getting too cute, and this proves it.