I was fighting bandits in the sewers when one of them went into a “cower” animation, and began screaming about how he had given up.
Given that I found his terror endearing, I deigned to spare him. I tried talking to him, to no effect. Then I tried sheathing my weapon – upon which the brigand thought he had a chance, and resumed hostilities with due haste!
Sadly, he did not offer to yield again before I slew him.
And so, the question remained unanswered: do enemies actually surrender, or was this just a clever ploy to catch me with my pants down?
It’s a ploy. You have to use your judgement. Honorable people will usually yeild and fall to their knees, if you leave them, they will revert to being a friendly. Bandits, in my experience, haven’t.