Is Lakoff and Johnson's theory of Coherent Metaphors powerful when it comes to any given pair of metaphors?
Rudyard Kipling's *Just So Stories 
are a collection of origin stories answering questions like "How did the leopard get his spots?" They've taken on the broader connotation that a clever enough person can come up with a plausible (enough) explanation for *anything*.
Critics often allege that Evolutionary Psychology is rife with just-so stories:
> Critics argue that many hypotheses put forward to explain the adaptive nature of human behavioural traits are "just-so stories"; neat adaptive explanations for the evolution of given traits that do not rest on any evidence beyond their own internal logic. They allege that evolutionary psychology can predict many, or even all, behaviours for a given situation, including contradictory ones. Therefore, many human behaviours will always fit some hypotheses. Noam Chomsky argued:
>> "You find that people cooperate, you say, 'Yeah, that contributes to their genes' perpetuating.' You find that they fight, you say, ‘Sure, that's obvious, because it means that their genes perpetuate and not somebody else's. In fact, just about anything you find, you can make up some story for it." – Wikipedia Criticism of evolutionary psychology / Testability
I'm pretty good at coming up with plausible-yet-bogus explanations that appeal because they're "out there" (unconventional, iconoclastic, heterodox). Of course, I only use this power consciously, and for good, but it's just barely possible I might unconsciously use it to justify the unjustifiable.