Quote Originally Posted by Drewski View Post
The funniest to me, is when you are sieging a town, and the ai is running its units around under missile fire and they are dying like flies, then suddenly they get the "glow" when there are only half a dozen left.

So you basically get promoted for dying
The engine tracks experience for individual soldiers rather than units (although morale at least is calculated on the unit rather than soldier basis). Promotion merely means an increase in the average experience of the unit. And the average can go up if the unit's rookies are taken out.