The problem is Mallett has shown little to no development in the limited time he has been on the field. He had poor footwork, poor ball placement, never had to go through progressions, and forced horrible throws everywhere.(which is pretty typical of elite arm strength QBs).

 

So you watch a few preseason games of his 2.5 years later and he still has bad footwork, bad ball placement, and shows terrible decision making. If you show virtually no growth after 2.5 years of tutelage under Belichick and Brady I think it's safe to say you just aren't going to make it. 

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