Officials said its apocalyptic connotation made clear that this was no ordinary road closure, scaring many people into staying home this weekend.
"The only way to reduce the number of cars in the system is to penetrate the consciousness of the motorists," Yaroslavsky said.
In light of the foreboding warnings, said Doug Failing, executive director of the Metropolitan Transportation Authority's highway program, "it would be nice to have a little bit of congestion."
He was joking, but his point was an important one. Public officials run the risk of becoming victims of their own success. Their messages have to be strong enough to produce action but credible enough so that people -- and the media -- trust them the next time.