First of all I don't trust Bellamy at all he has his own agenda.
I don't understand how pedestrians crossing in the morning will only add 10 seconds. That number does not add up, 10 seconds to cross 8 lanes of traffic? That seems impossible in my opinion.
Also this completely neglects the impact of traffic if it's grid locked and where you can't cross intersections on green lights because traffic is backed up.
Looks like fudged numbers to push his agenda.