Overlap Detection and Scheduling Conflicts
When two divisions both claim age 12, a 12-year-old belongs to neither — auto-assignment refuses to guess and parks them in the unassigned bucket. Overlap detection catches these boundary mistakes while you're still designing the structure, not on tournament morning.
What gets checked
Inside the Division Tree Builder, sibling divisions (divisions split from the same parent) are compared pairwise on their criteria:
- Age, weight, and experience — numeric ranges are checked for any shared values. Age 10–12 and 12–14 overlap at exactly 12.
- Rank — belt ranges are compared on the standard rank order. Brown–1st Dan and 1st Dan–2nd Dan overlap at 1st Dan.
- Gender and custom values — flagged when two siblings carry the same value.
The overlap warning
When overlaps exist, a warning button appears in the builder showing the count — 2 overlaps. Clicking it opens a detail view explaining the consequence in plain terms: a competitor falling in the overlapping zone matches two divisions and will land in the Unassigned bucket instead. Each flagged pair is listed with its parent division, the criterion involved, and the two division names, so you know exactly which boundary to adjust.
Overlaps don't block saving. You can save a tree with overlaps — the cost is only paid by competitors who actually fall in the shared zone. Fix them anyway: unassigned surprises on check-in day are the avoidable kind.
Fixing an overlap
Adjust the boundary values so sibling ranges are gapless and non-overlapping. If Division A covers ages 10–12 and Division B covers 12–14, change B to 13–14 (or A to 10–11). The same logic applies to weight and rank boundaries: each value should belong to exactly one sibling. Beware of the opposite mistake too — a gap (10–11 and 13–14, with 12 unclaimed) also strands competitors, just without a warning, so check the edges in both directions.
Any competitors already stranded appear in the Unassigned bucket. After fixing the ranges, run Run Reassignment… and they'll flow into the corrected divisions.
Scheduling conflicts
A different kind of overlap happens on the schedule: a competitor entered in both Kata and Kumite whose divisions run simultaneously on different mats. Taikai App reduces this risk structurally — when scheduling divisions across mats, sibling kata and kumite divisions are kept on the same tatami so shared competitors aren't called to two places at once. When laying out your mat schedule, keep divisions that share competitors on the same mat or in different time blocks.