Traffic and safety experts promote the zipper merge, saying it reduces congestion by 40%.

But here’s the problem: If not everyone does it, the system doesn’t work, and people stuck in traffic end up frustrated by those who seem to be flying past them.

And most Omahans definitely don’t do it.

“I am pro-zipper merge and have never lived in a place that was unable to zipper merge quite like Omaha,” said Lisa Chinn, a frustrated enthusiast. “It bothers me so much and it’s actually quite dangerous, especially when traffic backs up to one or both lights, and no one is willing to move into the other lane so that traffic in the perpendicular lanes can go past them.

“I’ve seen cars wait in the middle of the street while cars are trying to go past the opposite way.”

So if it’s so obvious and helps everyone, why do Omahans not do it? Why are there miles of backup on Dodge Street near the University of Nebraska at Omaha with a lane sitting empty?