1) no convalescence
2) no medium-term incapacitation
3) Schroedinger's wounding.
How would you solve those problems? Do you have examples that deal with them?
I am going to ramble on for a bit. I think that there are very good reasons some people have for not liking 4E, but I don't think it's because you can't narrate things a certain way.
I think it's because 4E takes Immersion to the shed and shoots it in the face.
1:
What do you mean by no convalescence? A mechanical reason for a
player to choose to have his PC sit in bed for an extended period of in-game time?
If so, then no, 4E doesn't do this.
That really has nothing to do with narration, though. I can narrate my guy being in bed with bad wounds. Mechanically, he's at full kick-ass power.
I can say, "After that last foray into the dungeon, my PC is tending to his wounds. His shoulder is separated and a few of his ribs are broken from the ogre's smash."
Then when the goblins bring the fight to the PCs, he picks up his sword and gets right in there. "He fights through the pain and dishes out some of it."
What a bad-ass.
There's nothing wrong with wanting a game to reward players who make the choice to have their PC recuperate for an extended period of in-game time. This is different from having
required narration. What it does is to force a different set of choices; ie. I'm wounded, so I rest; the game makes this a choice that I want to make.
4E doesn't ask players to make that choice. It says, "You're wounded (the colour) but you can still fight; you don't have to stay in bed; if you keep going then you can keep getting treasure and XP."
I think that when you say "You can't narrate convalescence" you're wrong; obviously you can. "My guy is hurt and he stays in bed." What you don't have is any game mechanic rewarding you for making that choice (and, in effect, it "penalizes" that choice because while you're in bed you're not getting any XP). So there's no reason
for the player to play the character as though he were wounded. Immersion is damaged.
(Then again, if you wanted to reward convalescence, you could always make a skill challenge... but I don't think that's what the way the game is set up.)
2:
If the story has someone getting severely injured, people yelling at him not to leave them while he is getting carried away on a stretcher, followed by him opening his eyes and weakly holding one of their hands...
PHB, pg 185:
Stabilize the Dying: Make a DC 15 Heal check to stabilize an adjacent dying character. if you succeed, the character can stop making death saving throws until he or she takes damage. The character's current hit point total doesn't change as a result of being stabilized.
This situation happens when the PC is either out of Healing Surges and/or can't access a Healing Surge, and has to make Death Saves. Not very common, but it can still occur.
3:
Imagine (to take an extreme example in the hopes that you will actually try to understand the issue) having a CN-Two-Face Warlord as your healer (recruiting sucked). Now the DM has to narrate (or, more likely, will simple stop narrating wounds altogether) wounds that *could* easily kill you (about 50% of the time, when the Warlord decides not the heal you), but could be recovered from by a guy yelling at you. Not easy.
DM: "You get slashed by the sword. 18 damage."
Fighter: "Oh, I'm down."
DM: "Ah, it's a bad wound, a deep slash across your chest from your shoulder to your hip. Your collarbone breaks and your blood flows freely, seeping from underneath your armour, and you collapse."
Warlord: "I yell at him: Get the hell up, you sissy! This is no time to be taking a nap!"
Fighter: "Um... the wound closes up?"
DM: "No, no. The wound's still there. He just inspired you to get up and fight on. And guess what - you're tough enough to do it."
Fighter: "What a bad-ass I am."
Warlord: "You're even more bad-ass than that. First, I use Knight's Move to get you back on your feet."
Fighter: "Sweet, I get up."
Warlord: "'Good, good!' I say. 'Now let's show him what we're made of!' Hammer and Anvil. If I hit, you get to make a free basic attack. And - yep, it's a hit! Add +3, my Cha bonus, to your damage."
Fighter: "I flex my hand on my sword and raise it above my head - yes, even though my collarbone is broken, I raise it high and grit through the pain - and smash it down on him in grim revenge, driven mad by the inspiring presence of the Two-Face Warlord here!"
4E PCs are bad-asses.
My point is that you don't have to worry that much. You might have to accept the (action movie) trope that people can grit their teeth and dish out the pain even when the chips are down. If you don't like that, then you'd probably have to be careful with your narration.