Sometimes, when I hit a roadblock in mechanical design, I'll stop working on the game for a while and wait for new ideas to seep in. Today, while I was reading the Dungeon Master's Guide for a campaign I may be starting, one of the passages in it evoked a bunch of associative thoughts in my head (like the ones Doctor House always gets). Suddenly, I figured out a way to streamline the mechanics train-wreck of realistic health and damage.
*The effect of an attack is based upon the gradient of success.
*Instead of having hit points, your character's toughness (or whatever name I give this value) reduces the gradient of success for certain attack types (mostly unarmed). Armor reduces the gradient of success from a more lethal range of attack types.
*Instead of increasing damage, power merely bypasses the effect reduction offered by armor or physical strength. This is possible because the effects for each gradient of success is static. For example, as long as you get +4, your unarmed strike will always result in a knockout (for extra nastiness, knock 'em out onto a very hard floor for a potentially serious injury or death), and your lethal weapon strike will always result in death. More powerful weapons will get death on 3.
*Ultimately, the formula for determining the Effect of an attack will be gradient of Success - (effect Reduction - Power), or E = G - (R - P).
*This method also spares me countless hours of smashing appliances in the house over trying to figure out a simple way to make a realistic body-targeting system. The thought of having hit points for each body area horrified me, especially if there were a large number of NPCs a GM had to keep track of.
*In fact, this method may allow me to make a very simple yet realistic burst fire mechanic.
New Combat Example
King Arthur and Lancelot circle each other, preparing to duel. They are both wearing armour and fighting with sword and shield. After his knights were soundly beaten by the graceful warrior, Arthur knew Lancelot would be more than a challenge for him (composure checked: passed).
Arthur moves into range to attack, and strikes at Lancelot's shield repeatedly. Lancelot chooses a safe maneuver and blocks with his shield to prevent the blows from knocking him off balance (reflex, bonus from shield: pass for each blow). On Lancelot's turn, he uses his shield to shove Arthur (dexterity). Arthur resists the push (strength + shield bonus = pass). Lancelot tries again, but uses his focus to improve the attack; arthur resists and uses his last combat action to improve his score (Arthur rolls 2, Lancelot rolls 4, which allows him to roll again and gets 3, so 3+3 = success). Lancelot pushes Arthur off balance and uses his last attack to strike Arthur in the head. The attack is successful (+4), but because of Arthur's helmet (-3 effect against the sword), the blow only stuns him. Lancelot is out of actions, so he cannot take advantage of it. On his turn, Arthur uses an action to recover, but in his anger from being struck, he makes a poor decision and takes a huge cutting blow at Lancelot(power strike; focus added = roll of 3 - power strike penalty of 2 = +1). Lancelot, having excellent dexterity, moves his shield in an arc to parry the blow instead of blocking, which knocks Arthur off balance, and then with the momentum, Lancelot uses the complex maneuver Reverse Parry to immediately follow up with a sweeping blow behind Arthur's knees, which trips Arthur. Lancelot could use his last attack to kill Arthur (floored opponent bonus negates 2 effect reduction of armor, not to mention an attack bonus, and since Arthur has no actions left, he's pretty much helpless), but he doesn't as Arthur huffs, "Yield! I yield!"
((Thus, the example demonstrates combat resolution without the use of hit points. This method, combined with the techniques-based actions, also results in an interesting meta-game effect. In other systems, it's common to see an, "You hit for x damage/ You miss" exchange representing what happens in combat. In the example above, combat is depicted in a very concrete, vivid manner in which the aforementioned descriptions can never happen, even with a less verbose GM. Damage and hit points are abstracts, but effects are not.))