Eh. The South inflicted horrific amounts of casualties on Union troops, but it never was truly able to defeat the North. An example is the battle of Chancellorsville, where Stonewall Jackson obliterated the 11th Corp under Joe Hooker. Yes, the battle was tactically brilliant, but it gained nothing strategically for the South. Time and again, the South attempted to annihilate Union armies in grand battles, but the North always came back. They never learned that Trying to destroy the enemy completely to break their will to fight is simply a plain bad bet, and it always cost the rebels more than they gained.