From my experience, most Americans apparently like to be stopped in the middle of the road for absolutely no reason. The more claustrophobic the traffic the more wonderful it is.
Is it any wonder, that often my trip to and from work, often takes into account the most rural avenue possible. Distance factors little into it. I would say time neither, but the longer, more rural route is often the time saver.
(doesnt help my town has apprently designed the traffic light system, to stop you at 90% of the lights if you go relatively around the speed limit.)