Microblog: This Ogre is Quantum, or The Unseen
In Luke Gearing's Wolves Upon the Coast, there is an ogre that lives on the isle of Ruislip, and can be encountered randomly within a three-hex radius of his shack. If a group of PCs split into two parties to explore the north of the isle, it's completely conceivable a GM might roll an ogre encounter for both parties. In the moment before deciding which PCs would actually encounter the ogre, who can't be in two places at once, it would be as if the ogre existed in a quantum superposition between both locations. But this quirk of random encounter tables, despite being "quantum," is not considered an example of the quantum ogre phenomenon.
In Charlie Kaufman's Antkind, a recluse named Ingo Cutbirth makes a three-month long stop-motion animation film, its impossible scope drastically increased by the fact that for every scene filmed, Cutbirth staged a vast number of other scenes that went deliberately unfilmed. These Unseen puppets are meant to make the work more resonant, but they may instead seem to the reader like an unwieldy complication deployed for an auteur's self-aggrandizement.
The "quantum ogre" is one of those blogosphere ideas that quickly outgrew the bounds of its enclosure. While I think the concept has value to a certain culture of play (though perhaps better formulated as "no paper after seeing rock"), the "quantum ogre" formulation conceals the fact that the problem does not come from the quantum-ness of the ogre. Principles of blorby, OSR play like "not all challenges will be perfectly balanced to a party's capabilities" can be undermined by things like excessive fudging of monster stats. But I do not think they will be harmed by the elimination of "prep for the sake of prep" or choices the players never even realized they had.