Hi Mathieu,
I can see how this comment is misleading (as it misled me too..). The short answer is that you can use Timer 0 in one-shot mode.
The other timers on the C28 have hardware support to stop the timer when in one-shot mode. As Timer 0 doesn't have this hardware support, this stub function is added so that you can use the Timer module APIs irregardless which Timer the application is using.