eli5: would adding more lanes to a freeway/busy street really ease congestion or would you still get bottlenecks?

Question

I mean theoretically adding a lane or two should allow more cars to flow through, or would bad drivers still cause bottlenecks/gridlock despite the added capacity?

In: 28

Answer 1

Adding a 6th lane to a 5 lane street may have limited usefulness.

Adding a 3rd to 2 lanes is going to be great.