I'm not sure why it would be reading "0.00 flat", but I don't think this should be considered an issue. If there is a fault in the VVT, the dash CEL will illuminate. Since the computer needs to know where the cam is at in the phase, it measures the cam angle. There are two parameters which should be looked at, which you should be able to find within VCDS:
- Cam adjustment specified
- Cam adjustment actual
If these are lock step (the same), there's no issue with your cam phasing. If they are different, there's an issue. An issue there can be for many different reasons, such as the wrong oil, carbon buildup, clogged oil passages within the phasing system, stuck lock pin, etc.
To maybe help you, here is a YouTube video I found which explains how the VW VVT system works.