Yes, it should be up to the translator, and depend on the intention of the translation:

Is the writer role-playing as a Klingon? Or pretending to be writing for an audience of Klingons?

Is the text aimed at new readers or experienced ones?
Is it actually being used to communicate, or is it being used as ornamentation?

Is it important that the text can be transliterated into pIqaD?
Is it important that the Terran words fit seamlessly into the written text?

Is it important that the Terran words fit seamlessly into the spoken translation?

In this sense, it isn't much different from writing in one's own first language; you use one style when writing for preschoolers, another when writing an e-mail to friends, still another when writing a scholarly article, and something different entirely when writing a post-modern rhyming parody of recapitulation theory.

> That's true, I agree. What bothers me most is that we now have a non
> canon word in this episode of Family Guy that could have been avoided.

That's always going to happen, though; from "GARR'DACK!" on The Simpsons, to "Krish-krush!" on Frasier, not to mention the mountains of Paramount Hol we have from official Star Trek productions.

I'm all for keeping close track of what is and what isn't canon, so that we have a common reference point to start from, but I don't think we should restrict our use of the language to suit people who clearly don't have much interest in learning it, anyway.

"Canon is the beginning of wisdom; not the end."

 ~ Spock, ca. 2293

//loghaD