The two lanes in the picture merge into one "center" lane. I've never seen that here in the states. Typically it is one lane merging into another lane. I'd wager the "merge into the shared center lane" makes the zipper protocol more obvious.
The zip system is used ubiquitously here - I didn't even know there were other systems, so I was curious to see what new thing the article was about. From what I understood, the alternative is not really a "system"?