There is a National Standard for driving which outlines what good driving is like. (There is also a National Standard for cycle training used by Bikeability)
The advantage of having such a standard is that drivers and driving instructors will be clear about how and why a rider positions themselves in the lane and riders clearer of their right to ride away from the kerb etc.
One question someone has raised against creating a National Cycling Standard is the risk that this may be used by prosecutors against cyclists who don't ride according to this standard in court (especially after the Charlie Alliston case). I understand that British Cycling and Cycling UK have this issue.
I think that recognising what good cycling looks like and having this standard hosted by the DVSA along with the other standards for other road users would help clarify may issues and perhaps over time reduce conflicts between drivers and cyclists