That is indeed the strategy, and it relies on the allies having pretty bad luck to smash up those stacks without losing 50% of your starting planes.
Germany can replace the planes, but not at the same time as it builds mechs, armor stax
Japan has even more planes, but it needs even more than Germany does because without them, its a paper tiger.
The problem with doing these stub attacks is if you lose more than 50% of your starting air power before turn 5, you will not be able to force your victory cities and strategic objectives. The consequences are felt several turns later (7,8), when you cant smash stax because you lost your mobile strikeforce.