I'm not saying 'entire protest invalidated' and agree that even with small random acts of property damage and a number of arrests there was value to the protest. But it's limited value - it's 'lots of people don't like the cuts and are willing to give up a Saturday' and where does that get us? It won't lead to a change of government policy.

I'm saying the better choice is to pick a form of campaigning that doesn't have a higher risk of being in the wrong place at the wrong time.

The 'what's happening where' feeds presumably rely on functional internet and mobile networks and on having a sufficiently good knowledge of the area to know how to get out of a potential trouble spot. You might have that knowledge of London, non-locals won't. What would you have done if the police had caused the networks to be blocked?