I am a proponent of using split formats. At my club's annual tournament, we have been using a split format for the past five years, and have been very happy with it. Kids don't have to wait as long between matches, and most parents enjoy spending only 1/2 the time in the gym (unless they have kids in both sessions, or are coaching).
I also did the bracketing at the Folkstyle Nationals, and a split format would not work there. With lots of 64-man brackets, there were some mats with only three brackets being wrestled on them, and most had only 4-5 brackets. By the final rounds, the only way to get the kids the required recovery time between matches is to be sure that all of the brackets are still wrestling at the end. Otherwise, we would have to schedule breaks between rounds, which would result in the tournament lasting significantly longer than it did. With many people needing to travel across the country, we didn't want to unnecessarily delay the end of the event.
