As I see it, the main issue with allowing this is that machine translations are often highly inaccurate. If you ignore that and only respond to the actual question, you will implicitly give the asker (and others at a similar level who may be reading the thread) the impression that the given translation is, indeed, correct. As such, if we are to consider interpretation / cleaning-up of machine translations as 'sufficient effort' by the asker, we should be ready to point out all the mistranslations when we do answer, in order to not give anyone the illusion that the translation is valid. However, this does result in some extra work, and it will also introduce unnecessary clutter into all of the answers that may be of relatively little interest to those who find the topic by using the search function (or as a search engine result) and click on it based on the title of the question.
So, in that case, it may be more optimal to simply remove the machine translation from the question, and only focus on explaining the usage of the Japanese word/phrase in the given example. If we do this, it will be the same as if the poster had never shown any effort in the first place, but then there will be no need to correct each and every arbitrary decision made by the translation software. This would simultaneously reduce the workload of the answerer(s) as well as improve the quality of the Q&A database (since even if the mistranslations are corrected, these corrections will often not be relevant to the topic at hand).
However, another option would be to simply treat interpretations of machine translations (i.e. translations that the asker cannot explain) in the same way as non-interpreted machine translations, i.e. as zero effort. This would be a logical extension of the current rules, since interpretation of the machine translation is simply interpretation of some English text, and there does not seem to be any reason to treat this as an effort to make sense of the original Japanese version.
Here's a real life example of a machine translation (or what actually turns out to be, I presume, the official English version of a line in a game; still, it is similar in the sense that zero effort was expended by the asker to produce it) that was previously given in a question. Original sentence in Japanese:
人類の進歩と調和に役立つもの・・・例えばディフレクターに代わる新しいエネルギーとかまぁ、そんなものですかな?
Translation given in the OP:
Personally, I believe it to be something of tremendous importance to mankind. Something that will help us better ourselves and the world. Perhaps, a new energy source, more powerful than our current refractors.
And here is an actual translation (that is not to say "a perfect one", but just "one that tries to be faithful to the meaning"):
Something that would help humanity achieve further progress and greater harmony... such as a new energy source to replace the deflector(s), or something like that, I guess?"
The question was about what the「そんなものですかな?」means in this context. The asker seems to have had no issues with the given translation, other than that. However, as I see it, in this case an answerer should, for the sake of not letting misinformation disseminate, point out that:
"Personally, (...)" is a mistranslation. There is no「個人的には…」「私としては…」「…と思う」「…あくまでも私の意見なんですけども」etc etc, so this is absolutely wrong.
"(...) I believe (...)" is a mistranslation. There is no「…と私は思っています」「…だろう」「…と信じている」 etc in the Japanese sentence.
"(...) (I believe) it to be (...)" is a mistranslation. The person is not making a statement about whatever they are talking about. The person is contemplating the words「人類の進歩と調和に役立つもの」, which were presumably spoken by someone else right before this sentence or at some earlier point in time.
"(...) tremendous importance (...)" is a mistranslation. We only have「役立つ」to work with here, and that means "to be useful for (something)", "to help with", "to facilitate", "to aid with" etc. There is no room for an adjective there.
"Something that will help us better ourselves and the world." is a mistranslation. There is no 'to better (...)' here, e.g.「より良くする」「改善する」「改革」 etc. There is no「世界」either. There is also no「私達自身」「我々」「人類を」etc, so "(...) ourselves" is a mistranslation as well.
"(...) more powerful (...)" is a mistranslation. Apparently it's supposed to correspond to「に代わる」, but there is no indication that an alternative energy source would have to be more powerful than the original.
"(...) our current (...)" is a mistranslation. There is no「今」「現」or anything that would point to "this point in time" even indirectly.
"refractors" ............... yeah, how about no. They're "deflectors". Still, this made it easy to figure out where the translation had come from.
Now, these would be fine (I guess?) in a liberal translation. However, there is zero reason for the asker to provide us with an extremely liberal translation as their "interpretation" of the original. And even if we did assume that this is fine if the asker did understand the original enough to be able to come up with a faithful liberal TL, they should certainly also provide a literal version, even if only for the sake of other people who might read the topic. If they do not do this, the responsibility falls onto the answerer, and I feel this is quite a bit of extra work and clutter that the Q&A database has no need for.