> while being essentially 1 person per step I think this estimate is incorrect. The article demonstrated otherwise. Also, people are willing to pack closer to

> while being essentially 1 person per step I think this estimate is incorrect. The article demonstrated otherwise. Also, people are willing to pack closer together when standing than when walking (and when walking than running!) Walking does increase the overall speed, but the study shows it's not enough for the increased space required. At least for British personal space requirements. Similarly, when driving, you need a certain amount of time between each vehicle. Yes, you can pack in with <1m space between bumpers in a stopped traffic jam, but you need many vehicle lengths to be safe at speed. For each mode of transport, there is an optimal speed and packing density. But you can't change one (speed) without affecting the other!