A long time ago (about 10 years ago), we lived 9 miles from the Nebraska border so attended a lot of tournaments in that state. Nebraska has their own rules and procedures for their kids tournaments and one of those is "block" wrestling. They also had most of the tournaments in a split-format which works hand-in-hand with block wrestling in my opinion.
Here is how they did it. The younger wrestlers (10 and under) were in the morning and the older wrestlers (HS and under) were in the afternoon. Weigh-in for the younger would be from 6:30-8:00 with wrestling starting at 9:00. The older group could come at anytime to weigh in after the younger ones were done but the scales would be closed at noon with wrestling for them starting at 1:00.
After all the wrestlers were weighed in, the brackets would be made with the closest 4 weights in one group....basically Block Wrestling. If there were more than 4 who were the same weight, then they would have an A and a B bracket.
Sounds great.....but not without it's own set of problems. There were some wrestlers (mostly in either the lighter or heavier side) who had to wrestle other kids who were up to 10 pounds heavier than them. And then lets say that you have 9 kids who all weigh within one or two pounds of each other but then have a jump where the next closest weight was 8 pounds heavier. Who decides on which kid gets moved into the bracket with the heavier kids? The one who is a better wrestler (A) or the wrestler (D) that just happened to be weighed on a scale that puts him 1/2 ounce heavier than the others?
And even with the Block scheduling, there were still some brackets that only had 2 or 3 kids in it because of the rule that you can't wrestle a kid who weighs more than X amount than you.
So even Block Scheduling has it's problems.