Test 4: Validating duplicate detection...
Found 1 duplicate groups:
  - John Smith: 35 duplicate(s)
WARNING: 'John Smith' has 35 duplicates, expected 2
WARNING: 'Sarah Johnson' has 35 duplicates, expected 1
WARNING: 'Michael Brown' has 35 duplicates, expected 1
WARNING: 'Jennifer Davis' has 35 duplicates, expected 1
WARNING: 'Robert Wilson' has 35 duplicates, expected 1
WARNING: 'Lisa Anderson' has 35 duplicates, expected 1

✓ All expected duplicate groups found
✓ Match reasons look reasonable
SUCCESS: Duplicate detection validated!