Cairo, it wasn't. But at about a quarter to four last Saturday afternoon, on a crowded backstreet in central London, something happened outside the Egyptian embassy that deserves at least a footnote in the annals of protest history. A crowd of students weren't kettled.

In the context of recent British protests, this was a near-miracle. At each of the previous four major student protests in London since the Millbank riot on 10 November, police have kettled – or, in their terminology, "contained" – thousands of protesters, preventing them from leaving an area for several hours, and often from accessing basic amenities such as food, water and toilets.

Police kettle protesters supposedly to quell violence, but protesters arguably only turn to violence out of frustration at being kettled. Most notoriously, police trapped hundreds of teenage schoolchildren inside a tight grid on Whitehall on 24 November – and only subsequently did a few of them smash up a police van abandoned in their midst.

Saturday's non-kettle, then, was a victory in itself. But the real excitement wasn't that it didn't happen – but how it didn't happen. It is difficult to pinpoint exactly why police and protesters behave in a certain way at a certain time, but one explanation for the kettle's failure to form lies with a new communications network, which launched that afternoon:Sukey.