Quick-access space should be assigned by frequency, not by warmth ranking
The cabin access layer should hold what gets used again and again during the day, not simply whatever seems most protective.
If a layer is only needed in a narrow time window, it often belongs in main luggage until that colder segment becomes certain.
In September, sudden discomfort often starts with wind before it starts with deep cold
At lakes, passes, grasslands and sunset stops, people often feel unstable first because they get exposed to wind quickly.
That makes a windproof shell a stronger default quick-access item than light down on many routes.
Fleece behaves more like a mid-layer, while light down behaves more like a reserve layer
Fleece is often best worn from the start or carried personally once the day has been judged.
Light down usually becomes valuable when the route clearly includes colder early departures, late returns, or more cold-sensitive travellers.
A stable setup keeps the shell in the cabin and promotes heavier warmth only when the day proves it
The stronger storage logic is often shell in quick access, fleece on the person or in a personal bag, and light down promoted forward only when colder conditions are already expected.
That reduces repeated luggage disruption and keeps cabin order cleaner over multiple days.