In real life, sometimes you would want to use hit and run skirmishes, say using just a horse archer/light calvary force, to slow down/inflict casualties on an invader. Would be useful to have "tactical withdrawal" button that leads your armies to execute a tactical withdrawal in good order (assuming none of your troops are engaged, routing or intercepted prior to leaving the battlefield) that allows you to use your remaining movement points in that turn, from the position of the battle.
Think I might add it to the suggestions list.
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