I've been wondering about that story as well. My own conclusion is that the experiment failed because the metric of average speed per passenger is wrong from a

I've been wondering about that story as well. My own conclusion is that the experiment failed because the metric of average speed per passenger is wrong from a passenger's perspective. People who stand probably don't care about a hardly noticeable increase in speed, whereas people who walk are annoyed by the very noticeable decrease in speed.