In my opinion, those are both bad choices. If you use the phrase to mean "raise the question", some pedants will silently dismiss you as a dunce, while others will complain loudly, thus distracting everyone else from whatever you wanted to say. If you complain about others' "misuse", you come across as an annoying pedant. And if you use the phrase to mean "assume the conclusion", almost no one will understand you.
My recommendation: Never use the phrase yourself — use "assume the conclusion" or "raise the question", depending on what you mean — and cultivate an attitude of serene detachment in the face of its use by others.
I absolutely hate the transition from spring to summer. My conversion into the enemy of my childhood self is complete. When I was younger this was my favorite moment of the year. Now it just means I don't get to do any of the things I like to do for three months. And it's a really bad time for me to encounter pet peeves, such as when journalists go to scientists to explain things that rhetoricians should be explaining.
I ran across this post the other day which I thought was really interesting. I find logical fallacies quite interesting, and this post seemed to promise that it would investigate not only the fallacy, but the origin of the phrase that we use for it.
The fallacy discussed is the Begging the Question fallacy, the only one that I've experienced, next to Argument from Ignorance, that students don't really ever understand. It's simply when you make your argument in a manner that assumes the more controversial and less agreed upon assumption within your claim has already been answered in your favor. Therefore, the opponents might "beg your pardon" on the way you dealt with that question.
I have no idea if this is historically accurate or what, but it's just how I rationalized it in my head when teaching it. At least I'm better off than the New Yorker, who thinks it means "to raise a question." So what do they do to solve their problem? They turn to a Computer and Information Science Professor to answer it.
This is my greatest pet peeve - how the media ignores rhetoricians, and how hard scientists are consulted to explain everything. Rhetoricians are notoriously bad about attracting the attention of the media as well, so the fault is on both sides. But if you are a rhetorician and you haven't talked to your media relations department at your University about what you study and what you can comment upon, shame on you.
So they ask the computer scientist (who has this blog, which is amusing until you realize that the sediment of working with computer languages informs his perspective on what "good" natural human language should look like) what he thinks and he responds by first claiming that begging the question is the same as the circular argument (Sorry professor, easy trap to fall in to but more studying on your part would spot the difference). Then he responds this way, which I simply must quote at length because it's too jaw-droopingly annoying to avoid:
As we can plainly see, this is why a rhetorician should be called in to answer such a question. For the Computer Scientist, the audience is unteachable, unchangeable, static, and with unproblematic and impossible to break ties to their understanding of the term. His solution is to "zen out" somehow about the words when they are misused. A quick check of the rest of his blog indicates just how easy that is to do - most every entry is about an annoying practice of language that is either worth our scorn or our laughter. This representative anecdote, in Burkean terms, shows us the limits of using any science - be it computer science, psychology, or any other go-to science for explaining "correct" use of language. The rhetorical moment of being able to trump your opponent, or broaden the audience's understanding is lost because "nobody will understand you."
That might work for computer languages, but identifying question begging, explaining it succinctly, and then using it as an argument itself as to why the opposition shouldn't be accepted is a powerful rhetorical move that just might work in a situation or two. Cultivating the ability to explain difficult, old, and complex ideas related to how we use language can boost one's ethos and improve the audience's appetite for looking a bit deeper into fallacies.
Of course, I agree with our noble computer scientist that adaptation to audience is vital. But at what point does it become pandering? At what point is the ethical duty to try to push that audience to richer understanding lost? I suppose for a computer scientist it makes sense to "re-code" the language to get rid of the annoying, meaningless "memory call" command (wow I really don't know enough about programming to write that last sentence). But for humans, language writes us. We didn't invent language, we were born with it. We came into "being," as humans, because of language. And that understanding is why scientific explanations of proper use of language will always be lacking.
We mold ourselves and each other with our words. This is what we lose when we crumble to the idea that "they just won't get it." It is good advice for getting a computer to do something though.