It is not enough to look at a stat line. Looking at a stat line is emphasizing results. Charlie Whitehurst could look shaky. He could double clutch and shuffle and still luck into long tosses and an impressive looking line. He could look poised. He could confidently pick out open receivers and suffer tip-drill interceptions and a crap quarterback rating.
What to look for? What to look for?
We should get 15+ passing attempts from Whitehurst. The most important quality to look for is decisiveness. I define decisiveness in this context as the culmination of confidence in the system, pre-snap reads and trust in his receivers, and that culmination is: take the snap, drop step if it's a drop, survey if it's shotgun, roll if it's a rollout and throw. Make a read and throw. We can wait with bated breath for the day Charlie is able to make three reads, boom boom boom, pump fake to draw the safety and zing a perfectly placed spiral just as Golden Tate breaks into a skinny post, but until our wildest fantasies come true, it's enough that he understands the system, can interpret how it interacts with the defense, finds an open man and zips it in.
The other quality, and we'll keep it simple for Whitehurst, is recognition of pressure. Recognition of pressure is a compromise. A quarterback can not waste time watching pass rushers. A quarterback also can not be oblivious to pressure. There are a few snaps in every game that a quarterback has to, has to, know that bad things are about to happen. Whitehurst hasn't shown that ability. He is rudimentary enough in his pocket awareness that he will get caught holding the ball away from his body even as the pocket closes all around him. It's debatable whether it's better to be oblivious to pressure or skittish, but neither is acceptable.
That is pretty much all I want from Whitehurst: quick, decisive passes and enough awareness in the pocket to avoid disaster.