I forget who it was said you didn't match up phase colors when running a 1-ph 120V branch from a 120/208 panel. Sounds as though it may be another of those regional practices or personal prefereces then.
I can sure see why the phase colors often don't get changed on a breaker move to another phase. One heck of a lot of work! So basically, when seeing a single-phase circuit, never believe what the phase color is telling you until checking it, right?
