If Wallace came into the year lacking fitness, he can get into game shape by playing, but he'll always be lacking a "base" that should have been developed during the preseason. Without a good base, any fitness he develops will deplete at a faster rate without planned rest periods.
I agree, Wallace needs to sit a game, or at least not start, so his legs get a rest. Camargo appears ready for a start, and I'd love to see Lewis get a go. Along the same lines, I wouldn't also mind seeing Callens get a 1game rest. Maybe for Callens, the Atlanta game isn't the best to rest, but managing the teams' legs is crucial for the guys that weren't here all preseason.