Moving sidewalks actually slow you down?

This was an interesting piece, in New Scientist because it points out that moving sidewalks or the formal name of "travelators" can actually make people move slower rather than faster when it comes to getting from point A to point B. I'll never forget my children's reaction to the first time they saw one of these horizontal escalators, and I admit in my recent travels I have noticed some people moving actually faster walking next to the travelator than those actually on the travelator. For me? I use them as a quick break, especially if I have to walk a rather long distance to pick up the next plane...