Four men and four women scaled the walls of Mr MacGregor's Muswell Hill home while he slept, unfurling banners to remind him of their long-running fight against the M11 link road, now under construction through Leyton and Wanstead.
As the street slumbered, a dozen people trotted up to the side of his neighbour's house with a long ladder. Within five minutes the eight were up on Mr MacGregor's roof, the banners were out and the ladder had been spirited away. The precision and organisation were flawless.
The neighbour emerged in his pyjamas, furious and demanding to know what was going on. Mr MacGregor kept his head down and his curtains drawn. A few minutes later the police arrived to be greeted by the protesters' liaison man, Patrick Field, smartly fitted out with suit, tie and clipboard. The two sides treated each other with courtesy.
'It's a perfect operation from our point of view,' he said. But might not the roof be damaged? 'Well, one of those up there is an architect.'
Mr MacGregor was more anxious and angry about the threat to his security represented by protesters knowing his address and demonstrating there than about any possible damage. He is believed to have urgently contacted the Home Secretary, Michael Howard.
The demonstration's largest banner depicted a road - the protesters said they were symbolically driving a motorway through Mr MacGregor's home. More than 300 houses are being demolished in the course of building the pounds 230m link road.
One hour after the protest began, Mr MacGregor emerged wearing a suit and a faint smile. As a small group of demonstrators on the ground shouted 'homes, not roads' he walked swiftly to his ministerial car and was whisked away.
It was the latest in a growing number of direct-action exercises designed to embarrass the Government over its apparent lack of a co-ordinated transport policy. Scotland Yard said 11 people were arrested but no charges had been brought by last night.
John Stewart, chairman of London-based Alarm UK, which co-ordinates the actions of 250 anti-roads groups across the country, said the Government's recent scrapping of about one- third of its road-building projects was partly due to a broad and growing opposition movement.
'We can't take all the credit, because the Treasury and Environment department are also applying pressure,' he said. 'But the Government has begun to realise that it isn't simply a radical few opposed to road-building. Opponents are of all ages, across all sections of race, class and profession. What's worrying the Government is the number of conservative people - with large and small Cs - from true blue areas that are joining our ranks.'
The movement is highly co- ordinated, even though it relies on donations and personal sacrifice for its funding. The No M11 Campaign has offices, fax machines, four telephones and 1,800 supporters on its database, ranging from lawyers and doctors to nurses and architects.
Yesterday, campaign members followed the lead of those in Wanstonia and Leytonstonia and declared a section of Fillebrook Road, Leytonstone, the Independent Republic of Euphoria, although they wrote to John Major saying they would still like the Queen to be their Head of State.