I have a hard time believing this (though I didn't read the article), but I suppose it's true. I grew up in Ontario. When I was in high school in the 90s, they really grilled us for spelling & grammar, especially "comma splices." I remember in particular the teachers "threatening" us by claiming that in university you lost something like 10% for each spelling mistake (though from my experience, they really didn't care outside of literature courses).
Where I work now we have a steady supply of co-op students. I remember we had this one student who made liberal use of chat-speak... over IM. I was actually pretty surprised to see a client-facing email of hers written perfectly eloquently.
If people are using 'cuz' in academic papers, they deserve to fail. Dang idiots.
Yeah, that's a pretty useless test. An "empty" song with one vocal and one instrument (I'm not talking about Billie Jean, I'm just stating a metric) wouldn't sound that wrong at a low bitrate. However, if you use a song with several distinct instruments, spanning high trebles and deep, smooth bass, and add in a clear voice, 48kbps will totally fall apart.
Basically, if you have content with detail & range at the same time, you require a higher bitrate. As far as how good it sounds, well, if the music requires a higher bitrate, it'll sound bad no matter what. If a codec is designed to make low bitrates sound "pleasing" vs. "accurate when possible," well, people might like the fact that it sounds pleasing. I don't know if AAC is designed to sound just pleasing at low bitrates, but it's not a bad idea since it can't sound accurate anyway.
It's like vinyl. People like vinyl because the process of converting vinyl waveforms to play on speakers is pretty easy, and purely analog. If you're going to listen to a CD with high quality speakers, you absolutely must have a great digital-to-audio converter somewhere in the chain. With an ordinary DAC, good speakers will just make the music sound very "discrete" and digital (cheap speakers won't reproduce that level of detail, but will probably sound better playing records than they do playing CDs).
"God is a comedian playing to an audience too afraid to laugh." - Voltaire