Can (and how does) one upgrade from Ubuntu 12.10 (now EOL) to 14.04 LTS?
I've found contradictory info about this online, some suggesting an intermediate upgrade to 13.10, while others suggest a direct upgrade to 14.04.
What would be the best procedure?
According to a top question on Ask Ubuntu, Ubuntu only supports upgrading from one version to the next version, or from one LTS version to the next LTS version.
Because 12.10 isn't an LTS (long term support) version, the only way you can upgrade is 12.10 -> 13.04 -> 13.10 -> 14.04 LTS. Therefore, you need two intermediate versions.
However, with a little bit of Linux experience, any way of upgrading/downgrading between different dpkg-based systems is possible and can be done relative easily. Even an Ubuntu to Debian conversion or suchlike isn't really hard with some well directed apt-get install
commands, but these are untested.
The paths supported by Ubuntu are better only because they are well tested. This is because it is of significant importance that an upgrade must be able to happen seamlessly and without any pain even for inexperienced users.