Playing on hard, I prefer to fight every single battle because my casualties are so severe when I autocalc.

In one battle on hard difficulty level I was attacked by a Roman army that I outnumbered 3 to 1, I was defending a mountain top in a blizzard and I had a far better general. I did an autocalc that gave me a crushing defeat, so I reloaded and fought the battle manually, effortlessly winning a heroic victory.