I think split format is a misnomer, "slotted" may be a better word for it, in my experiences, all the mats were committed for a specifice time period to that age group or groups of wrestlers.
Nigel, if you have not seen it happen, you wont believe the ease it creates on the wrestlers and the crowd involved. I think that it would solve a lot of the issues there are with the state and national tournament burn out that is created. For 32 yrs i thought there was only one way to do it, after seeing it happen, and the carry over on to the parents and the wrestlers it was great. How many times have you been to a big tourney and never saw anything but the gym. I was able to enjoy the areas we went to as well, my son was much more focused and i tell u another thing, the officals were fresher, the crowd calmer (Kansas is the only state in my experience where people actually think they can chew out an offical--try that in Nebraska, iowa or california,,u are out of there) and the vendors told me that they actually sold more items because the people coming in were fresh, positive rather than struggling through the day