Can one correctly hyperbolize the "take with a grain of salt" idiom?

There is a common (IMOE) English idiom, "take with a grain (or pinch) of salt", meaning one should be skeptical about the information it accompanies. Many times in the last year I've heard others try to exaggerate the meaning by changing the amount of salt in the idiom, for example:

• "I heard that restaurant is bad, but take it with a huge grain of salt"
• "Parking in that part of town isn't difficult; take it with many grains of salt"
• "Take it with an extremely tiny grain of salt, but my friend hated that movie."

I've understood this idiom to originate from an old antidote recipe, either real or allegorical. In this context, I don't understand how changing the amount of salt in the idiom changes its meaning. From conversational cues, I can sometimes distinguish whether the person means (1) "this isn't just hearsay, it's very unreliable" or (2) "I trust this source a lot, so it might be incorrect, but I doubt it". Many times, I cannot tell how the person means to change the idiom.

Question: Is there an explanation for the origin of this idiom which allows its meaning to change with the amount of salt described?

Follow-up: Is there a common understanding of the variances I've listed that have simply never been explained to me? E.g., more salt correlates with more suspicion warranted or vice/versa?

Solution 1:

My answer to this is that as language is alive, you will have salt added or taken out of it, regardless of the origins of the idiom.

One the arguments supporting this is that few people, except those with a particular linguistic interest, will know where an idiom originated. That should apply to any idioms in any languages whatsoever.

The second argument is that the whole point of language is getting your point across. That means manoeuvres not only are, but should and often have to be used so as to convey an intended message.

As a side-note from a non-native speaker, I see native speakers often use English idioms in the same way. So one hypothesis is that it may feel strange for native speakers if you are to take something with a "huge grain of salt", because of habituation.

I speak Portuguese as my 1st language, a language in which (at least in the Brazilian side of it) you'll hear dozens of versions of the same idiom. Especially in the countryside, people often coin their own versions of it. The further I go into the hinterlands, the more I see word coinage being used as well, although theoretically that should not happen, as there's no intrinsic word coinage mechanism in the Latin branch of Indo-European languages, as opposed to, say, in German.