I, too, was fascinated by that report, because I was not even aware of the secondary-grid concept -- I had thought that all distribution was radial. Those 120/208 secondary grid conductors must be huge to span city blocks, and locating which transformers are back-feeding a failed feeder must be a real challenge.
ShockMe77, you may have gotten to this part by now, but the feeders are 27 kV with maximum current ratings in the 600 to 900 amp range.
My hat's off to the guys that keep this stuff working.
