This is a gross oversimplification and has been misleading people for decades.
When communicating velocity for practical purposes we always do so in terms of relative velocity with a common frame of reference. We do this because to do otherwise is utterly ridiculous.
It is perfectly "legal" to travel at relative velocities faster than C - even if your starting relative velocities were zero. Now I understand and I assume you know: as you accelerate towards C, wierd things happen to the frames of reference of the traveller and external observer. But this really is irrelevant for practical purposes.
The important point is that to YOUR OWN measurements as taken BEFORE the trip, you travelled faster than the speed of light. This is the common and practical frame of reference that we would use to communicate our velocity. i.e. This was 100 LY away and I covered it in this amount of my time so I travelled at...
THAT, my friend, is what counts here for practical purposes of travel - as opposed to the esoteric world of the theory.
What many here are suggesting (practically speaking) is metaphorically akin to taking a velocity reading of your own body while sprinting on a supersonic jet and concluding you are travelling 6 km/hr as relative to the jet.
And it is a stupid thing to tell the average person because they fail to see the value in jet travel (durrr...I could never run to Paris!). (which is what has happened with space travel)