It won't work because we'd have "which path" information. You will only find superposition indirectly. No one has ever seen an object in two places (or states) at once. But the effects of an object existing in two states at once have been confirmed by thousands of experiments.
You claim to be in room C. You remember being in room C. We have videotape of you being in room C. Of course it's sensible that I believe you were in room C. You were never in a superposition, because we have measurements of you being in room C.
Now, if there was no way *at all* that anyone (not even you) could know what room you were in, *then* we would be in a regime where a superposition is possible. This situation is exactly analogous to the double-slit experiment, which I suggest you read up on. (Having not thought about it, though, I'm not sure how you'd perform the final measurement for your "room" experiment, but I'd be surprised if something couldn't be worked out.)
All said, your post indirectly touches on why the sort of thing the article is talking about is actually interesting. For very small things, like ions and photons, everything you describe about being in two positions simultaneously is absolutely true and confirmed experimentally. The kicker is that there's no fundamental principle that limits the size of what can be in a superposition. It's just that it's easier to do it with smaller objects, because it gets exponentially tricky to decouple the object from the outside environment, and erase any "which path" memory.