This seemed to be a trait of the war. When Van Dorn and Price attacked Corinth, after a long hot march, they were allowed to escape after their defeat, when Rosecrans had asked to follow. It was thought the Union men too tired and there was not enough water in the area, even though the Union forces, for the most part, had been stationary. My thought was if the Confederates could run the Union force could follow. It maybe their military training stressed that a hunter force must be superior in overall strength and health in order to go after a defeated foe. That was not Forrest's way of fighting since he was not educated in a military academy or school. He thought once a foe started running, continue attacking at all cost, no matter what the size or status of the enemy. I believe this is sound strategy, especially on your own ground.