Jeff Wilder said:
A 20th level character in 3.5 can easily have 200 HP. If that character is stabilized at -9 HP, it will take him 11 days to recover fully without the aid of magical healing; six days if he's tended full-time by someone with the requisite Heal skill modifier. It's not exactly realistic, but Ol' Veril is wagging his tail at the effort.
The character can take 11 days to recover, 11 days of letting his opponents plan against him while he can't go adventuring. Or he can take 21 minutes and 315 gp worth of wand charges. 315gp worth of consumables that, by the wealth by level guidelines, must be added to the next treasure horde the character recovers. The treasure horde that the character can go after on Tuesday (and then another on Wednsday, and then Thursday, etc), instead of waiting until the following Friday. Guess which option 95% of adventurers take?
The character doesn't even need magic items handed out like candy, they just need a cleric. First and second level spells aren't even useful to a 20th level character in combat. But they're sure useful to send a character's HP from zero to full in a few minutes.
This has been in the system since there was a class with access to healing magic. In 1st and 2nd ed players bullied other players into playing a cleric, and then
yelled at them if they didn't prepare enough curative spells to bring the party back to full. 3rd ed made a conscious decision to reduce this by allowing clerics to spontaneously cast curative spells so they didn't have to burn all their slots on preparing them and could sometimes do something useful. Players are still bullied into playing cleric, and they're still yelled at if they don't keep spell slots open (or keep a few wands available). Even worse, the 3.x cleric is substantially more powerful than the other classes. Now this is partially from some really stupid ideas related to access to divine spells (i.e. clerics have access to them all, all the time) it's also because the cleric as a class has been buffed to be more powerful as an incentive to get people to play the class (nobody wants to be the healer but we've made a big stick by making him a necessary part of the game, that didn't work, so lets just give out game-breaking carrots as incentive).
By giving players full HP on a long rest you make the need to hand out restorative items like candy just to let people play characters they want to play completely moot. You lose some realism, you lose some verisimilitude. But you gain players having the option of not playing a cleric without getting yelled at, and you keep clerics from being overpowered as a condolence to players who are yelled into playing them as healers, and that's much more important. This is why 4E is moving to the healing paradigm it's moving to. Maybe it's my background in quantum physics ("don't ask why, just calculate the damn wavefunction") but to me it doesn't matter if HP is physical wounds or fatigue or happy gnomes that cling to your body and absorb damage or whatever other logical cartwheels you have to go through to justify any of the HP systems to yourself, all I care about is that when they're in the negatives I am
very unhappy, and when they're high I'm happy. The fact that I can be happy without forcing someone into the dedicated healer role, and that the dedicated healers that are around don't have to become a CoDzilla is reason enough to support the new system. I hate to sound insulting, but your "feeling sick" at the fact that healing is more gamist and less simulationist is quite possibly the poorest argument in favor of setting players against each other and making a class start from the premise of being broken just so people will play it that I can think of.
And now, just to dig myself deeper into my happy little hole, I'll repeat something that I said before: a character falling out of a window, breaking his leg, and having to spend months recuperating is a
plot point. It's not a game mechanic. I don't want Aragorn to have to sit out the battle in Helms Deep because an orc in the previous battle got a lucky crit, I want my PC's fighting in battles I want them to fight in (as well as the battles
they want to fight in). If I want Good King Johan to get stabbed by the poisoned blade of an assasin, causing a wound that festers for months and weakens him in both body and mind, plunging the kingdom into chaos until the party partakes in a dangerous quest to recover the Waters of Elixia and heal him then I will put that in as
plot, I don't care what the healing rules are, I don't need to know the GP value of the dagger, the save DC of the poison, or how many levels of Fighter & Aristocrat are possessed by Good King Johan, I don't need to define the Waters of Elixia, all I need to do is establish that GKJ is injured, and the next quest is the party adventuring in search of his cure. In fact this is one of those things that
has to be plot centric, you're actually violating verisimilitude by not allowing the Paladin to completely destroy the point of the quest by using Remove Poison, and I'm OK with that.