This would be a new "terrain" type, think marshes and water but instead of -60% speed you get +10-15% when out of combat. Would help "rationalize" in-game logistics. Zergs and people confident moving in the open would get a significant movement buff going from keep to keep. The roads would be a major means of conveying large numbers which would focus mass RvR action on those lanes, while soloers/small groups/groups would have a clearer option of going out in the open or taking off-routes.
This would apply to PvE zones as well.
This would apply to PvE zones as well.