In 2014, I was in Denver for 4/20. It was a heady time. Colorado had recently legalized recreational cannabis, and High Times was capitalizing on the moment by throwing a two-day weed extravaganza known as the Cannabis Cup. I was an editor for them, and I’d been pressed into service along with the rest of the team to run the event. We knew it was going to be big, but we weren’t prepared for how huge and chaotic it turned out to be. Traffic was …