I think there are a number of individuals who would actually use metro to reverse commute but have the issue of "the last mile". If METRO allowed this individuals to purchase a parking pass that would be valid for overnight parking they could then use the METRO rather than driving the entire way. For instance, if I lived in DC but worked in Gaithersburg or Germantown, I could take the metro to the Gaithersburg station pick up my car and then go to work. Because of the time these spaces would still be available for regular commuters. They could use the same permit process.