It doesn't go agains release early, release often, as all geeks and early adopters will continue upgrading every six months, detecting bugs and improving the distro.
In fact, Ubuntu already does what the article says, the article just advocates a change in emphasis.
De article is not advocating turning Ubuntu into Debian. There are no PPA in Debian, so staying with an old distro really means using old software. With Ubuntu LTS+PPA, people would use solid software for everything except for thos programs that need to be upgraded more often.