About those boiling frogs...
Via Language Log quoting Kevin Drum, we learn that the boiling frogs story is, well, er, not true. Do read the whole post, which is knowledgeable and filled with great riffs, because I'm going to pull out just two quotes, which remind me of our current plight:
The frog story has no standard linguistic form — it's a conventionalized metaphorical narrative, not a conventionalized metaphorical phrase.
In that respect, it's like the original snowclone, which involves explaining that since the Eskimos have some large number of words for snow, so the members of some other group must have even more words for some substance, activity or concept believed to be typical of them. You can explain that in any words that you like, and it still works as a rhetorical gesture, as long as your audience doesn't object to the fact that its premise is untrue.
And as far as I know, there isn't really any suitable overall substitute for this linguistic abuse of Eskimos. ... Similarly, I can't think of any substitute for the false story about the Chinese characters for "crisis".
"Snowclone." Great concept.
Perhaps it's a rhetorical generalization that conventionalized metaphorical narratives are both false and unsubstitutable. This would follow from a couple of facts: people like to embellish stories to improve their fit to particular rhetorical circumstances, and rhetorical value is uncorrelated with truth (or perhaps negatively correlated). Based on those premises, you can show that Really Useful Stories will almost always be false, and also that Really Useful Stories will be the end point of a process of invention and memetic selection that's not easy to equal by mere intelligent design.
Speaking of the state of the discourse...