Spoiler Alert, click show to read:
Actually this is all my pet theory about auto-resolution battle mechanics, based upon oodles of experience auto-resolving and hitting bizarre snags when my lead units are weakened.
Sometimes all you have to do is solidify your troops by joining together weak units and all of a sudden the battle will auto-res better. I figured that out because it makes sense... you wouldn't send 20 units of depleted troops into battle, you would rather send 10 units at full strength to avoid routing.
But I really, really think I am on to something regarding auto-res calculations. You will get better results if you organize your stack properly. Much better.
In fact, I rarely if ever lose an auto-resolve battle ever since I've been subconsciously combining troops after every battle and purposefully managing stacks without generals.... and finally stacks with generals.
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