I agree with RedRiver, I have noticed a difference in taste between archery deer that died not knowing what happened, and deer taken on drives with dogs behind them.
That being said, I've heard that you just have to hang them long enough for rigamortis to set in, andthen come out, if you can move their limbs around the've aged enough. We usually hang them untill we have a few and its worth while to start butchering, we would lose too much time hunting if we stopped to process each animal when it was taken.