I don't think people like to have the rules of fiction spelled out in this way. They want to believe that the fictional world might be real, to see it thru the eyes of its inhabitants.
No doubt you're right, at least for a good chunck of players. (I always find it odd that such players choose D&D, though, rather than games like Runequest that have mechanics that are more "transparent" in this respect.)
My feeling - and I guess it betrays my Forge-iness - is that that sort of approach makes it hard to ensure a satisfying game. Because if everyone is busy being "in" the fiction, no one is responsible for making sure that it's worth being in.
It's not as if REH or Tolkien or Mallory just let their characters lose in the fiction - they contrived interesting situations that would put those characters to the test. I like the same sort of RPG play - a GM taking responsibility for framing interesting scenes, the players taking responsiblity for building PCs who, played in those scenes, will lead to exciting and unexpected stuff happening. Ultimately the mechanics are tools for achieving this.
To be an author is, in a way, to have fiction ruined for you because you can see all the techniques.
I don't write fiction, but I do write non-fiction. (I'm a humanities academic.) Maybe I just have a big ego! - but I can still be interested, even excited, by stuff I've written. The ideas and arguments intrigue, please, disappoint, sometimes even surprise me (the latter if it's been a while).
When it comes to GMing my game, it doesn't bother me that I've set up the situations deliberately to be interesting, and that the mechanics are designed to suppot this. Because the play that actually emerges from them is still engaging and often suprising. Like in my last session - the dwarf fighter-cleric was having his dwarven smiths reforge Whelm - a dwarven thrower warhammer, originally from White Plume Mountain - into Overwhelm - the same thing but as a morenkrad (the character is a two-hander specialist). I was adjudicating it as a complexity 1 (4 before 3) skill challenge. The fighter-cleric had succeeded at Dungeoneering (the closest in 4e to an engineering skill) and Diplomacy (to keep his dwarven artificers at the forge as the temperature and magical energies rise to unprecedented heights). The wizard had succeeded at Arcana (to keep the magical forces in check). But the fighter-cleric failed his Religion check - he was praying to Moradin to help with the process, but it wasn't enough. So he shoved his hands into the forge and held down the hammer with brute strength! (Successful Endurance against a Hard DC.) His hands were burned and scarred, but the dwarven smiths were finally able to grab the hammer head with their tongs, and then beat and pull it into its new shape.
The wizard then healed the dwarf PC with a Remove Affliction (using Fundamental Ice as the material component), and over the course of a few weeks the burns healed. (Had the Endurance check failed, things would have played out much the same, but I'd decided that the character would feel the pang of the burns again whenever he picked up Overwhelm.)
I've GMed a few item creation scenes over the years, in classic D&D, Rolemaster and 4e. While a relatively minor scene, this was probably the most intense I've GMed, and it certainly made the fiction - the dwarven artificers, the forge, the magic of the artefact, the prowess of a 16th level warpriest of Moradin - come to life.
It didn't hurt the experience that the rules (in this case, for skill challenges) have been deliberately designed to produce those outcomes. Because when play is actually going on, we're mostly not thinking at the meta-level - cetainly not the players, and not even me as GM, except when deciding the consequences for failing that Endurance check. We're thinking about the fiction, and what is happening. After all, it was my description of the situation, and the player "inhabiting" his PC and asking "What am I
not? - an artificer" and "What
am I? - the toughtest dwarf around", that led him to say "I want to stick my hands into the forge and grab Whelm. Can I make an Endurance check for that?"
I couldn't have run this little scene (maybe 15 minutes at the table) without mechanics that make improvisation and robust adjudication easy. That's not all of what I like about 4e, but it's a big part of it.