The point is that infantry are not going to effectively push an overwhelming cavalry rear-guard. The federals had an ad-hoc battalion of 200 cavalrymen. The Confederates had an ad-hoc brigade of 1100. Yet the federal cavalry still managed to push the Confederates 5 miles down the road to Mississippi Springs.

Not only would it not have been effective to pursue with infantry, it made no sense. By withdrawing down the Jackson-Raymond Road, Gregg's men had given McPherson an open path to the lifeline between Vicksburg and Jackson. McPherson could march to Clinton, interdict the railroad, and still be in Jackson before Gregg's men had regained any battle readiness.

Excoriating McPherson for not doing something that would have been pointless seems a little silly.