Yes, this is why I'm surprised Panama is also mentioned. I think the person who wrote the article is misinformed...Or maybe I am. All I can state for sure is that I always have to have a passport to leave Panama. I suppose if I had a State's drivers license, which I don't have, I could have entered the States with that license and kept my passport in my bag. At least, that's how I think I understand it. Strange.
Here's an example:
I had a brother in law who was working as a doctor for the Saudis. Every 6 months he was required to leave the country. He couldn't come home without losing his tax exemtion which required being out of the country 18 months.
He flew to Mexico, walked across the border using his California drivers license, took a cab to Brown Field and I flew him home.
He returned by the same route 2 weeks later.