In a Dungeon Magazine editorial from last year Chris Youngs talks about how Chris Perkins loves to use the coup de grace. He also talks about how it makes the enemies more memorable and satisfying to defeat. I couldn't agree more.
In D&D, regardless of the edition, death is the threat that gives the game meaning. The threat of your character dying is what makes the game fun to play, it is the other side of the risk/reward balance. D&D is not Burning Wheel or WoD, the players do not assign soft goals that have mechanical meaning to their characters. The goals of D&D are to find monsters and make their stuff your stuff. Though in recent editions the scope of the goal has been narrowed to killing monsters and making their stuff your stuff. Either way the reward is for putting yourself in physical danger and surviving. If you are never in actual physical danger the reward is meaningless.
I often have the monsters stop to kill a KO'd character. Do the players get mad? Yes. Do they really hate that guy and go after him with a vengence? Hell yes.
What coming to me in the Fall; Dwarven Forge
15 hours ago