Last but not least, if in doubt, then don't shoot. We're not overpopulated and killing does isn't that important.
This is our belief as well.
We simply made it a rule to only shoot does in the mornings away from food plots. Usually they are closer to you as you sit in a ladder stand or climber AND easier to ID in the broad daylight. And, as a general rule, are traveling in small family groups that make mature does more recognizable.