i counted another 6 (total of 12) vans when leaving the area of the demonstration. I then spoke to a couple of old ladies at a bus stop who informed me that buses had been diverted as the police had decided to close off the whole street and that sainsburys had kicked everyone out of the store (without giving them time to purchase their shopping) at about 4.00 apparently due to worries over the demonstration.
along with that and shutting off that entrance to the london overground it seems like the authorities did a pretty good job of causing disruption, even if they prevented the 2 (at one point 3?) separate groups of demonstrators and concerned passers by from having a wider impact.

Also it was nice to hear the english and greek chants echoed back from across the street by the larger number of demonstrators gathered there... the greek language sounds absolutely fantastic for angry chants by the way, even if like me you don't understand a word of it.