Part of the appeal of Dungeons & Dragons is its narrative sweep: the promise of following a character from 'That skeleton is moving, run!' to 'Hey, could you quickly marshal an army of skeletons to distract that god while I deal with this dimensional rift?' or thereabouts. But this literary sense of the game necessarily exists in parallel to the main action of the game, just as the 'meaning' of a play can't intrude on the performance of an individual scene. (The play's meaning isn't the actor's responsibility, it's [primarily] the writer's, secondarily the director's - another lesson for gamers, never mind actors.) When you're in the middle of an adventure or a section of a campaign your narrative consciousness foreshortens. Same thing when you're reading a well-written book or watching a skillfully crafted film - as long as it's not (sigh) self-conscious high literary metafiction, your consciousness of the form should dim, should (let's say) 'adverbize' (ha), your intellectual defenses dropping to heighten your emotional experience.
Which is why 'zero to hero' gaming isn't particularly well-suited to tabletop roleplaying: if you were to actually play Nodberg the Peasant on his very first adventure into the Nastywilde Forest in a 'realistic' way, Nodberg would be toast. You don't want realism, dear Gamers, you want to be fooled like any other reader/viewer/voter. You want permission to believe, to trust the storyteller enough to suspend your disbelief (defense mechanisms) and give in to the structure of the drama. You think you want the frustration of being a zero, but really you want (I betcha) a dramatization of your character's transformation to a somebody. A nonzero.
Let's say Nodberg heads out to the Chamomile Caves to pick some mushrooms for one of the members of his poly threesome, Daniellsworth. He runs across a troll. Hides in the cave, gets trapped when the troll comes in after him - can't get around the thing - so he comes up with a plan: he knows trolls track by scent in the dark, so he rubs the mushroom under his arms to make it musky, spits on it to make it sticky, and heaves it against the wall. The troll goes to track what it thinks is a drooling sweaty manburger; Nodberg slips by on cat feet, and is so suave in this moment of daring that he remembers to get another mushroom as he goes! (Daniellsworth and Vajitszil will be so proud that he kept his head.)
Now, dear Gamer, you're committed to 'realism,' or in any case think you are. If Nodberg is gonna make that kind of escape on a regular basis, he's gonna need a little more systematic knowledge, more practice, more drudgery (or - again - more luck, and if that's all you care about go play goddamn roulette). To actually evolve from Skinny Poly Nerdberg to Swarthy Nightblade Trapspringer Poly Smoothberg is going to take lots and lots of practice, which the rules of D&D don't cover, because this practice isn't mechanical (or rather the other way 'round: its in-game representation can't be mechanical - you really wanna roll the dice to determine how much educational benefit you derive from e.g. hitting 5,000 crosscourt backhands after school?). It's roleplaying, gotta be, and not the fun kind; the transition from 14th to 15th level is pretty easy to justify in game terms and you surely know how to roleplay it at the table, but the fine-grained character development from less-than-zero to almost-a-hero doesn't translate into fun dice-rolling experiences. The 'leveling up' mechanic doesn't scale to scared villagers. If that's the experience you want, forget your d20, grab a shovel and a shotgun, and leave your house; there are plenty of experiences awaiting you and if you play D&D you're (sorry folks) near-certainly just a scared villager yourself.
So here's an (I think) better idea, which has the added advantage of being blazingly obvious and indeed the default choice: if you wanna get the feel of zero-to-hero but don't want to cripple your character in the game's early stages to the point where he can't regularly do anything interesting (because he's got e.g. the proportional strength of a doily), make the challenges harder. Duh. A level 1 rogue trying to pick the pocket of the rare mountain-dwelling Midichlorian Familyfucker (it's got sharp teeth) is gonna need just as much ingenuity and crafty roleplaying as Nodberg in the cave - 'Your weapons: you will not need them' - but the game already has a well-defined system of rules for adjudicating your lvl1 rogue's actions without relying too much on handwaving and protean table compacts.
Old-school nostalgist/revivalists insist that 'fairness' and game balance are for little teenage bitches, but that's just revanchist carping of the 'Get off my lawn!' variety, the self failing to recognize itself. Your DM doesn't have to build 'fair' encounters - D&D 4e doesn't forbid anyone from putting a lvl15 trap in a roughly lvl2 dungeon - but it's nice for the system to be consistent (spanking a pre-linguistic baby that doesn't understand what it's done is sometimes necessary; spanking an older child that doesn't understand what it's done is child abuse. The contract is, 'You can trust that I have our interests at heart'). From the player's standpoint a little of the overarching paranoia and sense of malice is gone from 4e, that roller-coaster feeling that the world's against you, but the illusion-shattering feeling that the rules system is against you or 'mistaken' is gone too. Which might not make as much of a difference to the stereotypical Asperger's-spectrum troglodyte at whom D&D used to be aimed (I know a few of these guys; not all stereotypes are essentially wrong, though none are 'fair' - heh), who after all took some or much of his gaming pleasure from engaging with the rules themselves rather than primarily the storyworld; but in terms of bringing new people into the hobby, especially those raised on the emergent architectures and algorithmic procedures of computer/video games, this is a big necessary step forward.
Those girls and guys want the same zero-to-hero feeling you do, Gamer. The way to achieve it is to replicate not ineptitude but necessity, desperation, possibility. The 'Short Cut to Mushrooms' isn't thrilling because Frodo's useless or because he's statistically unlikely to be able to do anything about danger; it's thrilling because that Black Rider is terrifying and new and Other, and it reminds reader and hobbit(s) just how small we all are. (Hobbit readers get both barrels, alas.)
That holy emotion, that shift in perspective, the acknowledgment of smallness, comes not from size but from contrast. We're not essence-seers like the Buddha, we're edge-finders, pattern-matchers. (Personal nerd pride sidebar: Did I ever tell you I was very briefly a steganography researcher at a lab at MIT, in my capacity as level 1 computer programming acolyte? I would write GIMP plugins in Perl (TMTOWTDI) to detect 'random' scatters of encoded data in scanned images of dollar bills, to prevent counterfeiting. Did you know, further, that half the counterfeit money in Boston is printed on home inkjet printers?)
The sense of narrative sweep that pulls us into tabletop adventuring in the first place is best honoured and evoked not by the home fantasist's pretense to 'realism' but through the storyteller's craft of dramatic contrast and staging. 'Zero to hero' isn't an algorithm, it's an emotional experience, and Dungeons & Dragons (Fourth or any other Edition) is well-enough-suited to providing it. That the game has never been particularly good at simulating the travails of peasants-carrying-swords isn't a weakness of the game system, it's its nature: the attractive fantasies include enhanced abilities, an adopted past, great knowable defeatable enemies, danger that can be named, a call that can be understood, permission to ignore the mundane, the freedom to believe again that the dark cobwebbed passageway under the stairs runs at right angles to this world and emerges into another world entirely. That setup leaves so much narrative overhead, so much space for growth and exploration, that niggling about the difference between a hypothetical level -2 peasant and your underpowered-but-with-potential level 1 wizard seems silly or petty.
Well that's enough of that, I guess. Dangling possibility for next time: one reason 'old school' revivalists are so adamant about rulings-not-rules and save-against-death rolls and all those other forms of arbitrary ludic caprice is that
1) they're all middle-aged men and
2) they've played this shit a long time, have high-paying jobs, families, bills they pay responsibly every month; and
3) they miss being able - encouraged - to admit they don't know everything. They get their feeling of mastery elsewhere; they want danger, and ideally they want it in the form of dice rolls that go bad more often than the little teenage bitches' dice rolls go bad. What this obsession with tyrannical small differences says about the psychology of both potbellied-revanchists and teen-bitches I leave for the moment to the Reader(s). (Just so you know where I stand, I'm some sort of immensely sexy/wise potbellied bitch, rapidly balding to boot and not particularly good at paying bills, and I think the members of Tribes A and B should spend more time on ecstatic ritual and a good deal less time justifying themselves to their fellow tribesmen while slagging off [respectively] the poor deluded bitches and revanchists of Tribes B and A. Didacticism and outreach aren't the same thing - yet another lesson by the way for both actors and RPG-bloggers, boom! Not that my opinion matters much.)