Well, now you're just contradicting me.
And citing the relevant text from two core rulebooks. Or is rulebook text now not relevant to understanding how a game is meant to run?
To put it another way: what is the basis, in the 4e books, for assuming that there can be fire damage without the Fire keyword, or a scary effect without the Fear keyword? (Don't you remember the debate around the illusionist powers with the wonky keywords in Dragon magazine, that were fixed up before publication in Arcane Power?)
Or for denying that "story" - like the narration of a chasm, or a wall - doesn't affect resolution - eg via the falling rules, or the cover rules?
How does your table work out when the falling rules or the cover rules come into play, if not by refrence to the "story" - ie the shared fiction as it has been established at the table?
EDIT:
I don't really know what you think your leprechaun's power proves about the actual design sensibilities of 4e. By what standards are you asserting that it is a well-designed 4e power? Look at the Harper Agent theme in Neverwinter Campaign Guide, for instance: when the theme benefit is an item (a Harper pin) that confers a benefit it is statted as an item, not a power. Why is your magical leprechaun-housing shield not statted as an item?
And how do you resolve (say) attempts by another character (PC or NPC) to take down the leprechauns using an immediate, opportunity or free action? Summoning and conjuration powers carry rules that answer such questions.
I'm completely failing to follow your line of argument, and how it bears on the (in my view interesting) question of 4e's approach to fictional positioning - interesting in part because the importance of fictional positioning is I think one key feature that distinguishes a RPG from other, potentially similar, games like board games, wargames, etc.
FURTHER EDIT:
Does the following spell that I just wrote up prove that classic D&D wizards are broken?
Powerful spell of doom
Level: 1
Range: unlimited
AoE: 1 target
Effect: You speak the name of one person or creature you dislike and it immediately meets its doom: it dies, is crushed by a falling building, struck by a runaway cart, sinks to the centre of the earth, or otherwise meets a horrible end. This doom grants no saving throw.
I personally don't think so, give that my spell in no way complies with the design senibilities or examples that are part of classic D&D. Classic D&D wizards may or may not be broken, but my spell makes no contribution to that debate.