Ballast Point Calico Amber

I ended up in a Wetherpoons on Saturday and was pleased to see that their beer festival was on. Pick of the bunch was Ballast Point Calico Amber. It had the distinctive powerful citrus taste of American hops and was great on cask, which made me wonder why some people think beers like this taste best when they're kegged. I couldn't see how more carbonation and chilling would improve it myself. Oh well, each to their own.