# C1607 — Explain two large-span partitions as coarsenings of one path

## Question

Are7700+4900 and5600+7000 separate structures, or do they share a named common refinement?

## Sources

```json
[
  "three_MSS_12600_path.json",
  "C1488–C1492 shared7700 edge"
]
```

## Opened utc

2026-09-29T14:57:56.594205+00:00

## Results

```json
{
  "finest": [
    5600,
    2100,
    4900
  ],
  "Shem_SP_cut": [
    7700,
    4900
  ],
  "MT_Flood_cut": [
    5600,
    7000
  ],
  "whole": 12600,
  "identities": [
    "7700=5600+2100",
    "7000=2100+4900",
    "12600=7700+4900=5600+7000"
  ]
}
```

## Finding

Both follow from the same5600|2100|4900 path. Keeping the SP cut gives7700+4900; keeping the MT cut gives5600+7000.

## Reassessment

Identify the common unit for this selected path without claiming every spine node lies on it.

## Checks

```json
{}
```

## Closed utc

2026-09-29T14:57:56.594649+00:00

## Record provenance

Exact record hash: `0173bc26ef6159538e2ec8fa158e408608faae7f641c2cd915cce5c7cfe7a5de`

Source journal: `Research_Cycles/C1585_C1634/journal.json`