When the logistics stay runnable
- Both homes are close enough for school drop-off, practice, and sick-day pickup without doubling commute time
- Exchange count per fortnight fits work shifts — handoffs are not stacked on the same three evenings
- Both parents can own ordinary school nights: spelling homework, permission slips, morning alarms
- Gear duplicates exist at both addresses — cleats, chargers, and folder systems do not ride one backpack
- A written rotation names exchange times so pickup is not renegotiated by text every Sunday