Jeff Wilder said:
Every edition of D&D had long-term injury effects. HP loss took time (or magical healing) to heal. 4E has changed that by making HP recovery virtually instantaneous, thus removing a possible state ("injured and healing with time") from the game.
This is only partly true...
D&D has long had an inherent contradiction when it comes to HP.
Since 1e at least (didn't play before that) there was hand waving and various luck, stamina, dodge, and physical harm to explain hit points. Same old same old.
BUT
Somehow restoring stamina, luck, dodge all got wrapped into the physical harm idea.
There is really nothing realistic (speaking of stretching disbelief) to the idea that getting chomped by a dragon's jaws is somehow less deadly to a 10th level human than to a 1st level human.
In past editions, where disbelief actually got fouled up is that one hand said "HP reflect lots of things and of course you're not actually taking more damage" then the other hand said "You take forever to heal; heck damage doesn't heal overnight! Wait for 100 days or divine (literally) intervention."
The reason the 4e is more "realistic" and consistent is not because it has changed anything about the first hand but because it has made the second hand match. This could have gone either way. They could have made HP purely a reflection of physical injury and tied in conditions and extended healing. That would have also made the system more consistent.
I like the current way. If I want my PCs in a hospital, I will use a plot point to get them there.
DC