I think that's one of the reasons 4e really works for my group. What you're calling the 'narrative burden' is viewed by us as an opportunity to be creative. We provide the narrative that describes/explains/positions the mechanics within the in-game fiction. We prefer to do this, mainly because we prefer the
shi stuff we make up ourselves over that of some game designer who doesn't share our influences, sense of humor, and naked, adulterated brilliance

!
For example, in the absence of a satisfying explanation of how the 4e paladin's marking/divine challenge worked, I added/substituted my own, which was clever, vulgar, and wholly inappropriate for publication in a game aimed, at least in part, at kids. And thus one of our campaign's great running jokes was born, not to mention the part of the characterization of an entire race and culture.
In this way, D&D 4e resembles the HERO system. Powers are described almost entirely in mechanical terms; the fiction is up to the players. In HERO, the rocket launcher used by an insurgent and the boomerang used by Captain Koala --which hits every target in a radius-- could have the exact same mechanical description. Their difference would reside entirely in how they were described, ie in the mechanics attached to the fiction at run-time. This is a plus in my book, not laziness or lack of concern. It's a smart and deliberate choice.
I like systems that leave room for the player's fiction. They're more flexible.