Rarely does a film have 2 huge flaws, destroying pivotal moments

Rating: 5/10 (5 January 2007)

But alas, this one does.
First of all, there's no point reading this if you've not seen the film unless you trust me entirely. I'm reviewing this to broadcast my opinion to those who may not realise its two critical errors.
FIRSTLY. John Anderton discovers, with the help of the precogs, that he will kill Leo Crow (a man he does not even know). This is the ONLY THING that causes Anderton to go looking for his victim. In other words the precogs led HIM to the discovery of the man he is supposed to murder. Without the aid of the precogs, Anderton would not have gone looking for Crow and would therefore have committed no murder. So why was one predicted?
SECONDLY. At the end, when Lamarr Burgess is face to face with Anderton, Anderton gives Burgess a lecture in how he can change his future if he wants to, saying "No doubt the precogs have already seen this". But how would Burgess know he was supposed to kill Anderton? Did he see the pre-vision? Did Anderton see it? No. Therefore neither of them knew for sure that Burgess would kill Anderton. In the end, Burgess turns the gun on himself. Which means that he was never destined to kill Anderton. The precogs could have refrained from making the prediction and it would have made no difference. So, again, why was this murder predicted?
This isn't even taking into account other, smaller, yet silly flaws, such as: why was the missing person's case of Anne Lively never pursued? Or why didn't anyone else in Pre-crime remove Anderton's security clearance (he was still able to get through the doors by the use of his eyes)?
Poor, poor film. Probably the worst I've ever seen in terms of storyline.