The Joy of Healing
The best fights in RPGs are the ones that last multiple rounds. They allow a back and forth to develop and characters can spend time setting up interesting effects and tactics.
To have long and interesting fights game designers have 3 main routes available to them. Lots of defences, lots of health or lots of healing.
Lots of defences are used in games such as WFRP (parry, dodge, toughness), Savage Worlds (toughness, soak rolls), etc. Each blow that lands has to then do enough damage to break through the second line of defence. This is considered realistic but often leads to long fights where neither side appears to be achieving anything and then a 'lucky' blow gets through and the target collapses. Since this form of game design is often linked with exploding dice (re-roll and add on highest result possible) it sometimes creates the situation where the best fighter achieves 'nothing' but the weak second ranker gets the killing blow. Alternatively you hit issues where the defences raise so high that the target becomes near unkillable and certain characters are forced to sit out of a fight.
Lots of Health was used by 3rd ed D&D. High con dwarven barbarians could easily get health into the multiple hundreds. The downside to this method is the lack of fear in the player since they can see all their defences intact. It's only after a full day adventuring when the defences are low that the players start to fear. To get round this 3rd ed designers upped the damage output from the enemies but that just meant you return to the initial problem where people can withstand few attacks and so the fights have to be short. It also has the downside that certain archetypes are no longer valid (Raistlin type weak mages - since you need lots of health to survive by design)
4th ed is going the route of lots of healing.
Healing is handled by 'Healing surges'. Each character gets a number of these per day (6+con mod for Rogues, more for fighters). Each healing surge heals 1/4 of the characters hit points. Each character can activate a 'second wind' ability once per encounter (and once every few minutes outside battle) which allows them to use one of their own healing surges. Healing potions, heal checks and magical healing all trigger of the TARGETS healing surges (magical spells can give bonus hit points on top of the base surge).
This has a number of interesting effects (or at least so it appears to me)
1) Tactical feedback. In previous editions the decision to rest was made by the mage or the cleric. If either of them ran out of spells then the party was pretty much forced to stop. The interesting case was the cleric - if the front line fighters used poor tactics and suffered excessive wounds it was the cleric that got blamed for running out of spells. Now it's clear to see who is burning through their per day resources and so the party can adjust tactics to adapt.
2) Life on the edge. A 15th level fighter might have 120 hitpoints. During the fight they might often get knocked down into the low double digits resulting in a much more thrilling feeling than a fighter with 360 hitpoints but who has less access to healing.
3) The cleric is freed from being a walking band aid. Each character has a second wind ability they can use themselves. Standard healing rolls can also aid recovery. This means the cleric is free to devote more of their time to the adventure rather than watching over his flock (although since most characters will only have access to one second wind per encounter he better not ignore them completely )
4) Cure light wounds does! One oft commented on thing about D&D is CLW heals a low level character back to full but heals virtually nothing on higher level characters. Now since it activates a healing surge it heals at least 25% on all characters (although at low levels the bonus hp on top will have more of an effect than on higher level characters)
5) Noble sacrifice. A paladins Lay on Hands now allows them to donate one of THEIR healing surges to the recipient - a very nice thematic ability.
6) Keep pushing on! There are only so many triggers for healing surges so it is very unlikely that all of them will be spent in one fight. This means the characters can recover after the battle and keep going. As the day progresses and everybody uses up healing surges the group can modify tactics to utilise their remaining resources more efficiently. (I have a nice mental image at this point of the scared mage standing by the door looking back at the tired and beaten fighters leaning against the walls, barely able to hold their weapons, hoping that this time the door leads out and not to more danger)
[It's probably worth noting that hitpoints are viewed much more as stress / fear / morale / tiredness / luck / will to continue than physical pints of blood. Hitpoints have never been clearly defined in any edition but the ease with which the numbers go up and down in 4th ed stresses their metaphorical more than physical nature. One hp is being on your knees, exhausted and barely able to hold your sword - not lying on the ground trying to hold your guts in. Unless you want to describe it that way ]
