A rarely stated, but fairly common, belief here is that some tropes are rigid, and that the only variation comes with Playing with a Trope. Or some here think that most tropes are rigid, unless "Sliding Scale" is in the name. But it's not really true at all (also the reason we have The Same but More).
Even in the most narrowly defined Sub Tropes, there is plenty of room for variation, even when playing straight. And there can even be degrees of how the trope is applied, which is certainly the reason we don't allow The Same but More.
Two of the most common variations for a trope are the scale, and the importance in the story. But there are quite a few other ways to allow for trope variations.
The only actual thing rigid about tropes is the cutoff between one trope and another, or at least that is what we are striving for. Even when it involves Super Tropes and Sub Tropes, or if there is overlap with another trope, those tropes are still separate.
So the next time you think a trope is separate from another trope, make sure the line is clear. If it's not, you didn't make a mistake, other than underestimate how flexible tropes are.
Contrast Square Peg, Round Trope.
To best illustrate this concept, examples should be straight uses, with only some playing with them.
- All Just a Dream has quite a broad scope. It can be used for a single scene (the use least likely to annoy fans), entire episodes, entire seasons (Dallas), or even the entire series (St. Elsewhere). It can be a regular dream (The Wizard of Oz), a psychotic delusion told by an Unreliable Narrator (The Cabinet of Dr. Caligari), or even a "simulation" (Family Guy; 6th season, episodes 4th and 5th). Newhart managed to make fun of this, and crank it up even further by claiming that series was the dream of a character (played by the same actor) in another series.
- Xanatos Gambit and Batman Gambit are both about specific types of ingenious plans. The thing is there is nothing saying they have to be of a certain scale. Using these plans could involve just getting a promotion from your boss, to world conquest.
- In terms of Malevolent Architecture, Console Roleplaying Games tend to have loads of enemies, but rarely any hazards in the buildings, save for the occasional lava floor. On the other hand, Tomb of Horrors is infamous for having loads of traps in every room.
- Sex Sells has a wide range, from just attractive people in a picture, to acts that just scream "DOES THIS REMIND YOU OF ANYTHING?"