There are reports that say Johnny Manziel is undraftable to many teams.
The Cardinals could take advantage of this. Mr. Steve Keim drafted Tyrann Mathieu, who had obvious concerns off the field. So far, Mathieu has been able to stay clean, and he looks like the steal of the draft so far, making an impact in both games. He's a model citizen, and hasn't caused any problems in the locker room, or away from it.
Would the Cards take the same risk on Manziel?
The talent is obviously there. He's improved as a pocket passer, and frankly, is a better passer than scrambler. Bruce and Moore, the quarterback gurus, could coach this kid up. After a couple years of sitting behind Palmer, he could be dangerous, and wreak havoc on the NFL like Aaron Rodgers did.
This is a risk-reward situation, but I think the reward outweighs the risk. If coached right, he could be the next Cardinals quarterback for a decade.