VDOT's order of priority, which you can hear about once an hour on WTOP during a big storm, is to keep main arteries clear, then to move to important road, then secondary roads, then down to the neighborhoods. This is a lousy plan, especially when, as has been true for nearly every significant storm I've experienced in the last 20 years, VDOT more or less insists on plowing the main roads down to clean pavement before it moves to lesser streets.
I know the theory is that the main roads have to be kept clear for emergency vehicles, but in practice that doesn't matter if those vehicles can't get into the neighborhoods. If one of my neighbors had had a heart attack on the Saturday of the big storm, having Fort Hunt Road plowed would have done no good at all - there were 30 inches of snow on my street, rendering it impassable.
I grew up in a place where it snowed frequently, and they had a much more practical approach - everything got plowed in the first few hours and then regularly after that. The main roads got plowed more often (say twice for every time a street in the neighborhoods got plowed), but the plowing teams planned to hit every single street on a regular basis until the storm was over. It was a much better way to keep the streets clear and passable than VDOT's approach, and it had the extra benefit of making the load lighter for the plows on the passes through the neighborhoods.