I agree we need to see him in a full game.
But what do I know, DC Cardsfan says that's nonsense, the coaching staff knows full well what he can do because of practice, the only people who "need" to see him play are the fans and our opinion doesn't matter.
Considering how few reps backup QB's get in the NFL during the season I would argue being promoted even for one start makes a big difference. 3 weeks ago SF fans wanted Ken Dorsey, not Tim Rattay, to replace Jeff Garcia, now they're all talking about what can we get for Garcia in trade so we can start Rattay.
The Cards need to find out once and for all what they have in McCown and the only way to do that is start him a few games. I think Blake is a much better QB but he's been around he knows the situation, if he'd played better and the team was 6-4 and not 3-7, this wouldn't be coming up. I believe ultimately we'll find out McCown is not the answer, but remember Atlanta thought that when they traded Favre and Green Bay wasn't all that high on Aaron Brooks when they traded him. Some guys don't show in practice what they do in games, I don't think McCown fits but the only way to be sure is to play him.