Critical Mass for cars?

What if, on an agreed upon day, 1,000 drivers were to strategically position themselves in groups of 50 cars at 20 major thoroughfares throughout the city, occupy each lane of those thoroughfares, and proceed to obey the speed limits and all other regulations; i.e., not blocking the box, full stops at stop signs, etc.? Bullying SUV drivers who'd like to pass and drive 20 mph above the posted limits would be blocked. With full gas tanks, and another 1,000 relief drivers, this civilizing action could affect both morning and evening commutes. We'd certainly slow traffic down somewhat, and the police couldn't say any laws were being broken; their hands would be tied. In addition, this would be an irresistible story to the press; we'd get massive coverage from every major media outlet. What's the argument, that there's a basic right to break the law? I'd like to organize this and make it happen; if you'd like to participate, email me here. This would definitely get attention—and produce results.