I made it close to two hours once, while working at the same time. I speak french and they don`t speak it very well thus it was perhaps easier than you to keep them hooked up. He was quite angry when he understood he had been played all along. I hoped that saved a few people from getting caught by that scheme!
Tip of the hat, monsieur.
Laughing at them as they scream is a nice reward; I also hope it makes them more likely to dump a real mark, thinking they are being played, when the victim takes too long to con or isn't moving fast enough.