What The Hell Is Going On Here?
The real question is why are you so annoyed by him? Take a moment to look around our hypothetical train car. There's the guy behind you trying to teach his girlfriend to pronounce "Doritos" with correct Spanish phonetics. There's the conductor announcing the name of the next stop for the third goddamn time. Why is the guy on the mobile phone the one who's starring in grisly crime scenes in your mind?
Our problem with public cell phone conversations has nothing to do with how cool he thinks he is, or even his stupid voice. It's all in our heads.
Above: Not what we meant.
Science has proven that hearing half a conversation, as you're forced to do when close to a cell phone user, is inherently more distracting to the human brain. In one experiment, people were asked to try to concentrate on a task in total silence, and then while overhearing two people conversing with each other. They performed equally well both times. But when half a conversation was played, performances dropped dramatically. Another study showed that people on public transport recalled more details of a one-sided conversation than a two-sided one, even if they'd been trying to ignore both.
The human brain likes things to be predictable, and it can't really relax and "tune out" something that doesn't make sense. You might notice yourself trying to fill in the other half of the phone conversations you overhear. It's the same mechanism that makes it so hard to walk away after you've seen the first 15 minutes of an episode of CSI or Law & Order: The brain naturally hates leaving questions unanswered. Suddenly, you're trying to solve a puzzle instead of concentrating on how little you give a shit about the exact drunken position he passed out in last night.
Just how the fuck did that horse make her spend a year at college?