When side venting equipment is mounted in typical cabinets without side panels or dividers even maintaining the recommended distance between the equipment does not provide adequate cooling in a cold-aisle/hot-aisle environment. The problem with this approach is that it allows much of the exhaust of one switch to enter the intake of the next switch.
When using the Mighty Mo cabinet airflow baffles the intake air is always supplied from the cold aisle and the exhaust is directed by the baffles to the hot aisle. The use of filler panels on the rear rails in addition to the full height airflow baffles eliminates the recirculation of hot air within the cabinets.
Adding divider panels does little to improve the cooling in a cold-aisle/hot-aisle environment. This approach allows both the cold aisle and the hot aisle to provide air to the intake of the equipment. As the hot air is exhausted it recirculates back to the intake side of the equipment. Again each switch is receiving less cool air as you go down the row.