If you think about it, running seven days per week and practicing smart recovery techniques seven days a week (think running is your job) is basically running seven days a week with seven days off per week. It's the people (like myself) who juggle running and working where a full time job where rest days or active recovery (my favorite) come into play.
The key is to A.) work less B.) work physical jobs but not too physical
We under estimate the stresses of daily lives. If we stripped the stress of society off our running sheath, we'd be recovering every day of the week.
In all, sleep and sedentary rest followed by active recovery (or easy running) are the best things to focus on. After that, focus on hard workouts and nutrition. Then focus on strength, especially if you don't run hills or natural surfaces.
Doubles are a fine way to get away with a day or two off as well. For mortals, run 8 times a week for 6 days of running and one day of intense cross training. If you can do that and have running workouts that are pushing it but you still feel like jumping out of bed like a ninja warrior 5 days a week, then you are on your way to great running.