What is the nuance between "préparer qqch à qqn" and "préparer qqch pour qqn"?

Question

In a different question, an answerer said this:

In all of those uses, the dative pronouns correspond to noun phrases marked by the preposition à. In one of those uses, it overlaps with the (semantically motivated) use of the preposition pour to mark beneficiaries of an action:

Je prépare un bon petit plat à mes enfants > je leur prépare un bon petit plat

Je prépare un bon petit plat pour mes enfants > je prépare un bon petit plat pour eux

But as you can see from the correspondence above, this semantic overlap doesn't mean that there is a syntactic link between "je leur prépare un plat" and "je prépare un plat pour mes enfants". Presenting it as the pronoun leur replacing the noun phrase "pour mes enfants" is simply wrong. They're two different sentences that mean almost the same thing.

Given that English has only one preposition to mark the idea of Beneficiary for this sentence ("I am preparing a small dish for my kids"), I'm wondering: What is the (nuanced) difference between

• "Je prépare un bon petit plat à mes enfants" vs
• "Je prépare un bon petit plat pour mes enfants"

?

That is, is there a nuanced difference .. in meaning? .. in register? .. in typical contexts one is used more than the other? etc

Answer 1

The context can require a particular choice that will carry a nuance, but ever so small that I believe it hardly possible to make an argument about its value. Usually there is no nuance.

• Je prépare un bon petit plat pour mes enfants, pas pour elle car malgré tout le mal que je me donne elle dénigre vicieusement ma cuisine.

"À" would not be quite as expressive, and possibly not quite idiomatic; it is not a preposition that communicates its semantic function as vividly as others, this being due, at least in part, to the great number of functions that have been piled up upon it (TLFi). Therefore the idea of someone being a beneficiary is made more salient by the use of "pour". I would not argue against the use of "à" in that sentence but I definitely prefer "pour".

Anyway, let's notice that "à" is not at all proper in front of pronouns when use in this sense (pour).

• Je les prépare pour elle. Je les prépare à elle.

This shows again that this preposition, in some of its uses, is lacking somewhat in specificity, in clarity as to what it communicates.