The diverging diamond interchange comes to St Louis.

[PoorManQ45]

Are there any lights near this interchange that would cause traffic to backup into it?

If so, that could get really bad in a hurry!

*edit* wait a minute! The traffic backed up at these lights could cause the entire interchange to clog up. This would be wonderful to see people coming directly at you.

People know they're not supposed to enter an intersection if they can't get all the way through, but they still do!

[Jesda]

So far, it seems like it just moved the congestion a few feet back. Traffic doesn't seem to flow faster, at least not enough to justify the cost of this project.