This article does make a good point. It has been my experience that highway traffic can move more quickly when people do not change lanes. I have seen this happen a couple times in very snowy conditions; the traffic density was such that it should have been stop & go traffic; however, due to the large amount of snow between each lane, everyone pretty much stayed in their lane. This made traffic go at a steady 20-25 mph. (Note that the set of circumstances in which snow can cause traffic to speed up is very rare).

The main problem that this article does not address is bottlenecks. Even with a perfect system, it is impossible to keep a constant speed if there is a large influx of traffic at a certain point or the road narrows to fewer lanes.